// stb_truetype.h - v1.14 - public domain
// authored from 2009-2016 by Sean Barrett / RAD Game Tools
//
//   This library processes TrueType files:
//        parse files
//        extract glyph metrics
//        extract glyph shapes
//        render glyphs to one-channel bitmaps with antialiasing (box filter)
//
//   Todo:
//        non-MS cmaps
//        crashproof on bad data
//        hinting? (no longer patented)
//        cleartype-style AA?
//        optimize: use simple memory allocator for intermediates
//        optimize: build edge-list directly from curves
//        optimize: rasterize directly from curves?
//
// ADDITIONAL CONTRIBUTORS
//
//   Mikko Mononen: compound shape support, more cmap formats
//   Tor Andersson: kerning, subpixel rendering
//   Dougall Johnson: OpenType / Type 2 font handling
//
//   Misc other:
//       Ryan Gordon
//       Simon Glass
//       github:IntellectualKitty
//
//   Bug/warning reports/fixes:
//       "Zer" on mollyrocket (with fix)
//       Cass Everitt
//       stoiko (Haemimont Games)
//       Brian Hook 
//       Walter van Niftrik
//       David Gow
//       David Given
//       Ivan-Assen Ivanov
//       Anthony Pesch
//       Johan Duparc
//       Hou Qiming
//       Fabian "ryg" Giesen
//       Martins Mozeiko
//       Cap Petschulat
//       Omar Cornut
//       github:aloucks
//       Peter LaValle
//       Sergey Popov
//       Giumo X. Clanjor
//       Higor Euripedes
//       Thomas Fields
//       Derek Vinyard
//
// VERSION HISTORY
//
//   1.13 (2017-01-02) support OpenType fonts, certain Apple fonts, num-fonts-in-TTC function
//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
//   1.11 (2016-04-02) fix unused-variable warning
//   1.10 (2016-04-02) user-defined fabs(); rare memory leak; remove duplicate typedef
//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use allocation userdata properly
//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
//                     variant PackFontRanges to pack and render in separate phases;
//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
//                     fixed an assert() bug in the new rasterizer
//                     replace assert() with STBTT_assert() in new rasterizer
//
//   Full history can be found at the end of this file.
//
// LICENSE
//
//   This software is dual-licensed to the public domain and under the following
//   license: you are granted a perpetual, irrevocable license to copy, modify,
//   publish, and distribute this file as you see fit.
//
// USAGE
//
//   Include this file in whatever places neeed to refer to it. In ONE C/C++
//   file, write:
//      #define STB_TRUETYPE_IMPLEMENTATION
//   before the #include of this file. This expands out the actual
//   implementation into that C/C++ file.
//
//   To make the implementation private to the file that generates the implementation,
//      #define STBTT_STATIC
//
//   Simple 3D API (don't ship this, but it's fine for tools and quick start)
//           stbtt_BakeFontBitmap()               -- bake a font to a bitmap for use as texture
//           stbtt_GetBakedQuad()                 -- compute quad to draw for a given char
//
//   Improved 3D API (more shippable):
//           #include "stb_rect_pack.h"           -- optional, but you really want it
//           stbtt_PackBegin()
//           stbtt_PackSetOversample()            -- for improved quality on small fonts
//           stbtt_PackFontRanges()               -- pack and renders
//           stbtt_PackEnd()
//           stbtt_GetPackedQuad()
//
//   "Load" a font file from a memory buffer (you have to keep the buffer loaded)
//           stbtt_InitFont()
//           stbtt_GetFontOffsetForIndex()        -- indexing for TTC font collections
//           stbtt_GetNumberOfFonts()             -- number of fonts for TTC font collections
//
//   Render a unicode codepoint to a bitmap
//           stbtt_GetCodepointBitmap()           -- allocates and returns a bitmap
//           stbtt_MakeCodepointBitmap()          -- renders into bitmap you provide
//           stbtt_GetCodepointBitmapBox()        -- how big the bitmap must be
//
//   Character advance/positioning
//           stbtt_GetCodepointHMetrics()
//           stbtt_GetFontVMetrics()
//           stbtt_GetCodepointKernAdvance()
//
//   Starting with version 1.06, the rasterizer was replaced with a new,
//   faster and generally-more-precise rasterizer. The new rasterizer more
//   accurately measures pixel coverage for anti-aliasing, except in the case
//   where multiple shapes overlap, in which case it overestimates the AA pixel
//   coverage. Thus, anti-aliasing of intersecting shapes may look wrong. If
//   this turns out to be a problem, you can re-enable the old rasterizer with
//        #define STBTT_RASTERIZER_VERSION 1
//   which will incur about a 15% speed hit.
//
// ADDITIONAL DOCUMENTATION
//
//   Immediately after this block comment are a series of sample programs.
//
//   After the sample programs is the "header file" section. This section
//   includes documentation for each API function.
//
//   Some important concepts to understand to use this library:
//
//      Codepoint
//         Characters are defined by unicode codepoints, e.g. 65 is
//         uppercase A, 231 is lowercase c with a cedilla, 0x7e30 is
//         the hiragana for "ma".
//
//      Glyph
//         A visual character shape (every codepoint is rendered as
//         some glyph)
//
//      Glyph index
//         A font-specific integer ID representing a glyph
//
//      Baseline
//         Glyph shapes are defined relative to a baseline, which is the
//         bottom of uppercase characters. Characters extend both above
//         and below the baseline.
//
//      Current Point
//         As you draw text to the screen, you keep track of a "current point"
//         which is the origin of each character. The current point's vertical
//         position is the baseline. Even "baked fonts" use this model.
//
//      Vertical Font Metrics
//         The vertical qualities of the font, used to vertically position
//         and space the characters. See docs for stbtt_GetFontVMetrics.
//
//      Font Size in Pixels or Points
//         The preferred interface for specifying font sizes in stb_truetype
//         is to specify how tall the font's vertical extent should be in pixels.
//         If that sounds good enough, skip the next paragraph.
//
//         Most font APIs instead use "points", which are a common typographic
//         measurement for describing font size, defined as 72 points per inch.
//         stb_truetype provides a point API for compatibility. However, true
//         "per inch" conventions don't make much sense on computer displays
//         since they different monitors have different number of pixels per
//         inch. For example, Windows traditionally uses a convention that
//         there are 96 pixels per inch, thus making 'inch' measurements have
//         nothing to do with inches, and thus effectively defining a point to
//         be 1.333 pixels. Additionally, the TrueType font data provides
//         an explicit scale factor to scale a given font's glyphs to points,
//         but the author has observed that this scale factor is often wrong
//         for non-commercial fonts, thus making fonts scaled in points
//         according to the TrueType spec incoherently sized in practice.
//
// ADVANCED USAGE
//
//   Quality:
//
//    - Use the functions with Subpixel at the end to allow your characters
//      to have subpixel positioning. Since the font is anti-aliased, not
//      hinted, this is very import for quality. (This is not possible with
//      baked fonts.)
//
//    - Kerning is now supported, and if you're supporting subpixel rendering
//      then kerning is worth using to give your text a polished look.
//
//   Performance:
//
//    - Convert Unicode codepoints to glyph indexes and operate on the glyphs;
//      if you don't do this, stb_truetype is forced to do the conversion on
//      every call.
//
//    - There are a lot of memory allocations. We should modify it to take
//      a temp buffer and allocate from the temp buffer (without freeing),
//      should help performance a lot.
//
// NOTES
//
//   The system uses the raw data found in the .ttf file without changing it
//   and without building auxiliary data structures. This is a bit inefficient
//   on little-endian systems (the data is big-endian), but assuming you're
//   caching the bitmaps or glyph shapes this shouldn't be a big deal.
//
//   It appears to be very hard to programmatically determine what font a
//   given file is in a general way. I provide an API for this, but I don't
//   recommend it.
//
//
// SOURCE STATISTICS (based on v0.6c, 2050 LOC)
//
//   Documentation & header file        520 LOC  \___ 660 LOC documentation
//   Sample code                        140 LOC  /
//   Truetype parsing                   620 LOC  ---- 620 LOC TrueType
//   Software rasterization             240 LOC  \                           .
//   Curve tesselation                  120 LOC   \__ 550 LOC Bitmap creation
//   Bitmap management                  100 LOC   /
//   Baked bitmap interface              70 LOC  /
//   Font name matching & access        150 LOC  ---- 150 
//   C runtime library abstraction       60 LOC  ----  60
//
//
// PERFORMANCE MEASUREMENTS FOR 1.06:
//
//                      32-bit     64-bit
//   Previous release:  8.83 s     7.68 s
//   Pool allocations:  7.72 s     6.34 s
//   Inline sort     :  6.54 s     5.65 s
//   New rasterizer  :  5.63 s     5.00 s

//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
////
////  SAMPLE PROGRAMS
////
//
//  Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless
//
#if 0
#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
#include "stb_truetype.h"

unsigned char ttf_buffer[1 << 20];
unsigned char temp_bitmap[512 * 512];

stbtt_bakedchar cdata[96]; // ASCII 32..126 is 95 glyphs
GLuint ftex;

void my_stbtt_initfont(void)
{
	fread(ttf_buffer, 1, 1 << 20, fopen("c:/windows/fonts/times.ttf", "rb"));
	stbtt_BakeFontBitmap(ttf_buffer, 0, 32.0, temp_bitmap, 512, 512, 32, 96, cdata); // no guarantee this fits!
																					 // can free ttf_buffer at this point
	glGenTextures(1, &ftex);
	glBindTexture(GL_TEXTURE_2D, ftex);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, 512, 512, 0, GL_ALPHA, GL_UNSIGNED_BYTE, temp_bitmap);
	// can free temp_bitmap at this point
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
}

void my_stbtt_print(float x, float y, char *text)
{
	// assume orthographic projection with units = screen pixels, origin at top left
	glEnable(GL_TEXTURE_2D);
	glBindTexture(GL_TEXTURE_2D, ftex);
	glBegin(GL_QUADS);
	while (*text) {
		if (*text >= 32 && *text < 128) {
			stbtt_aligned_quad q;
			stbtt_GetBakedQuad(cdata, 512, 512, *text - 32, &x, &y, &q, 1);//1=opengl & d3d10+,0=d3d9
			glTexCoord2f(q.s0, q.t1); glVertex2f(q.x0, q.y0);
			glTexCoord2f(q.s1, q.t1); glVertex2f(q.x1, q.y0);
			glTexCoord2f(q.s1, q.t0); glVertex2f(q.x1, q.y1);
			glTexCoord2f(q.s0, q.t0); glVertex2f(q.x0, q.y1);
		}
		++text;
	}
	glEnd();
}
#endif
//
//
//////////////////////////////////////////////////////////////////////////////
//
// Complete program (this compiles): get a single bitmap, print as ASCII art
//
#if 0
#include <stdio.h>
#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
#include "stb_truetype.h"

char ttf_buffer[1 << 25];

int main(int argc, char **argv)
{
	stbtt_fontinfo font;
	unsigned char *bitmap;
	int w, h, i, j, c = (argc > 1 ? atoi(argv[1]) : 'a'), s = (argc > 2 ? atoi(argv[2]) : 20);

	fread(ttf_buffer, 1, 1 << 25, fopen(argc > 3 ? argv[3] : "c:/windows/fonts/arialbd.ttf", "rb"));

	stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer, 0));
	bitmap = stbtt_GetCodepointBitmap(&font, 0, stbtt_ScaleForPixelHeight(&font, s), c, &w, &h, 0, 0);

	for (j = 0; j < h; ++j) {
		for (i = 0; i < w; ++i)
			putchar(" .:ioVM@"[bitmap[j*w + i] >> 5]);
		putchar('\n');
	}
	return 0;
}
#endif 
//
// Output:
//
//     .ii.
//    @@@@@@.
//   V@Mio@@o
//   :i.  V@V
//     :oM@@M
//   :@@@MM@M
//   @@o  o@M
//  :@@.  M@M
//   @@@o@@@@
//   :M@@V:@@.
//  
//////////////////////////////////////////////////////////////////////////////
// 
// Complete program: print "Hello World!" banner, with bugs
//
#if 0
char buffer[24 << 20];
unsigned char screen[20][79];

int main(int arg, char **argv)
{
	stbtt_fontinfo font;
	int i, j, ascent, baseline, ch = 0;
	float scale, xpos = 2; // leave a little padding in case the character extends left
	char *text = "Heljo World!"; // intentionally misspelled to show 'lj' brokenness

	fread(buffer, 1, 1000000, fopen("c:/windows/fonts/arialbd.ttf", "rb"));
	stbtt_InitFont(&font, buffer, 0);

	scale = stbtt_ScaleForPixelHeight(&font, 15);
	stbtt_GetFontVMetrics(&font, &ascent, 0, 0);
	baseline = (int)(ascent*scale);

	while (text[ch]) {
		int advance, lsb, x0, y0, x1, y1;
		float x_shift = xpos - (float)floor(xpos);
		stbtt_GetCodepointHMetrics(&font, text[ch], &advance, &lsb);
		stbtt_GetCodepointBitmapBoxSubpixel(&font, text[ch], scale, scale, x_shift, 0, &x0, &y0, &x1, &y1);
		stbtt_MakeCodepointBitmapSubpixel(&font, &screen[baseline + y0][(int)xpos + x0], x1 - x0, y1 - y0, 79, scale, scale, x_shift, 0, text[ch]);
		// note that this stomps the old data, so where character boxes overlap (e.g. 'lj') it's wrong
		// because this API is really for baking character bitmaps into textures. if you want to render
		// a sequence of characters, you really need to render each bitmap to a temp buffer, then
		// "alpha blend" that into the working buffer
		xpos += (advance * scale);
		if (text[ch + 1])
			xpos += scale*stbtt_GetCodepointKernAdvance(&font, text[ch], text[ch + 1]);
		++ch;
	}

	for (j = 0; j < 20; ++j) {
		for (i = 0; i < 78; ++i)
			putchar(" .:ioVM@"[screen[j][i] >> 5]);
		putchar('\n');
	}

	return 0;
}
#endif


//////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////
////
////   INTEGRATION WITH YOUR CODEBASE
////
////   The following sections allow you to supply alternate definitions
////   of C library functions used by stb_truetype.

#ifdef STB_TRUETYPE_IMPLEMENTATION
// #define your own (u)stbtt_int8/16/32 before including to override this
#ifndef stbtt_uint8
typedef unsigned char   stbtt_uint8;
typedef signed   char   stbtt_int8;
typedef unsigned short  stbtt_uint16;
typedef signed   short  stbtt_int16;
typedef unsigned int    stbtt_uint32;
typedef signed   int    stbtt_int32;
#endif

typedef char stbtt__check_size32[sizeof(stbtt_int32) == 4 ? 1 : -1];
typedef char stbtt__check_size16[sizeof(stbtt_int16) == 2 ? 1 : -1];

// #define your own STBTT_ifloor/STBTT_iceil() to avoid math.h
#ifndef STBTT_ifloor
#include <math.h>
#define STBTT_ifloor(x)   ((int) floor(x))
#define STBTT_iceil(x)    ((int) ceil(x))
#endif

#ifndef STBTT_sqrt
#include <math.h>
#define STBTT_sqrt(x)      sqrt(x)
#endif

#ifndef STBTT_fabs
#include <math.h>
#define STBTT_fabs(x)      fabs(x)
#endif

// #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h
#ifndef STBTT_malloc
#include <stdlib.h>
#define STBTT_malloc(x,u)  ((void)(u),malloc(x))
#define STBTT_free(x,u)    ((void)(u),free(x))
#endif

#ifndef STBTT_assert
#include <assert.h>
#define STBTT_assert(x)    assert(x)
#endif

#ifndef STBTT_strlen
#include <string.h>
#define STBTT_strlen(x)    strlen(x)
#endif

#ifndef STBTT_memcpy
#include <memory.h>
#define STBTT_memcpy       memcpy
#define STBTT_memset       memset
#endif
#endif

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
////
////   INTERFACE
////
////

#ifndef __STB_INCLUDE_STB_TRUETYPE_H__
#define __STB_INCLUDE_STB_TRUETYPE_H__

#ifdef STBTT_STATIC
#define STBTT_DEF static
#else
#define STBTT_DEF extern
#endif

#ifdef __cplusplus
extern "C" {
#endif

	// private structure
	typedef struct
	{
		unsigned char *data;
		int cursor;
		int size;
	} stbtt__buf;

	//////////////////////////////////////////////////////////////////////////////
	//
	// TEXTURE BAKING API
	//
	// If you use this API, you only have to call two functions ever.
	//

	typedef struct
	{
		unsigned short x0, y0, x1, y1; // coordinates of bbox in bitmap
		float xoff, yoff, xadvance;
	} stbtt_bakedchar;

	STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
		float pixel_height,                     // height of font in pixels
		unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
		int first_char, int num_chars,          // characters to bake
		stbtt_bakedchar *chardata);             // you allocate this, it's num_chars long
												// if return is positive, the first unused row of the bitmap
												// if return is negative, returns the negative of the number of characters that fit
												// if return is 0, no characters fit and no rows were used
												// This uses a very crappy packing.

	typedef struct
	{
		float x0, y0, s0, t0; // top-left
		float x1, y1, s1, t1; // bottom-right
	} stbtt_aligned_quad;

	STBTT_DEF void stbtt_GetBakedQuad(stbtt_bakedchar *chardata, int pw, int ph,  // same data as above
		int char_index,             // character to display
		float *xpos, float *ypos,   // pointers to current position in screen pixel space
		stbtt_aligned_quad *q,      // output: quad to draw
		int opengl_fillrule);       // true if opengl fill rule; false if DX9 or earlier
									// Call GetBakedQuad with char_index = 'character - first_char', and it
									// creates the quad you need to draw and advances the current position.
									//
									// The coordinate system used assumes y increases downwards.
									//
									// Characters will extend both above and below the current position;
									// see discussion of "BASELINE" above.
									//
									// It's inefficient; you might want to c&p it and optimize it.



									//////////////////////////////////////////////////////////////////////////////
									//
									// NEW TEXTURE BAKING API
									//
									// This provides options for packing multiple fonts into one atlas, not
									// perfectly but better than nothing.

	typedef struct
	{
		unsigned short x0, y0, x1, y1; // coordinates of bbox in bitmap
		float xoff, yoff, xadvance;
		float xoff2, yoff2;
	} stbtt_packedchar;

	typedef struct stbtt_pack_context stbtt_pack_context;
	typedef struct stbtt_fontinfo stbtt_fontinfo;
#ifndef STB_RECT_PACK_VERSION
	typedef struct stbrp_rect stbrp_rect;
#endif

	STBTT_DEF int  stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int width, int height, int stride_in_bytes, int padding, void *alloc_context);
	// Initializes a packing context stored in the passed-in stbtt_pack_context.
	// Future calls using this context will pack characters into the bitmap passed
	// in here: a 1-channel bitmap that is width * height. stride_in_bytes is
	// the distance from one row to the next (or 0 to mean they are packed tightly
	// together). "padding" is the amount of padding to leave between each
	// character (normally you want '1' for bitmaps you'll use as textures with
	// bilinear filtering).
	//
	// Returns 0 on failure, 1 on success.

	STBTT_DEF void stbtt_PackEnd(stbtt_pack_context *spc);
	// Cleans up the packing context and frees all memory.

#define STBTT_POINT_SIZE(x)   (-(x))

	STBTT_DEF int  stbtt_PackFontRange(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, float font_size,
		int first_unicode_char_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range);
	// Creates character bitmaps from the font_index'th font found in fontdata (use
	// font_index=0 if you don't know what that is). It creates num_chars_in_range
	// bitmaps for characters with unicode values starting at first_unicode_char_in_range
	// and increasing. Data for how to render them is stored in chardata_for_range;
	// pass these to stbtt_GetPackedQuad to get back renderable quads.
	//
	// font_size is the full height of the character from ascender to descender,
	// as computed by stbtt_ScaleForPixelHeight. To use a point size as computed
	// by stbtt_ScaleForMappingEmToPixels, wrap the point size in STBTT_POINT_SIZE()
	// and pass that result as 'font_size':
	//       ...,                  20 , ... // font max minus min y is 20 pixels tall
	//       ..., STBTT_POINT_SIZE(20), ... // 'M' is 20 pixels tall

	typedef struct
	{
		float font_size;
		int first_unicode_codepoint_in_range;  // if non-zero, then the chars are continuous, and this is the first codepoint
		int *array_of_unicode_codepoints;       // if non-zero, then this is an array of unicode codepoints
		int num_chars;
		stbtt_packedchar *chardata_for_range; // output
		unsigned char h_oversample, v_oversample; // don't set these, they're used internally
	} stbtt_pack_range;

	STBTT_DEF int  stbtt_PackFontRanges(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges);
	// Creates character bitmaps from multiple ranges of characters stored in
	// ranges. This will usually create a better-packed bitmap than multiple
	// calls to stbtt_PackFontRange. Note that you can call this multiple
	// times within a single PackBegin/PackEnd.

	STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample);
	// Oversampling a font increases the quality by allowing higher-quality subpixel
	// positioning, and is especially valuable at smaller text sizes.
	//
	// This function sets the amount of oversampling for all following calls to
	// stbtt_PackFontRange(s) or stbtt_PackFontRangesGatherRects for a given
	// pack context. The default (no oversampling) is achieved by h_oversample=1
	// and v_oversample=1. The total number of pixels required is
	// h_oversample*v_oversample larger than the default; for example, 2x2
	// oversampling requires 4x the storage of 1x1. For best results, render
	// oversampled textures with bilinear filtering. Look at the readme in
	// stb/tests/oversample for information about oversampled fonts
	//
	// To use with PackFontRangesGather etc., you must set it before calls
	// call to PackFontRangesGatherRects.

	STBTT_DEF void stbtt_GetPackedQuad(stbtt_packedchar *chardata, int pw, int ph,  // same data as above
		int char_index,             // character to display
		float *xpos, float *ypos,   // pointers to current position in screen pixel space
		stbtt_aligned_quad *q,      // output: quad to draw
		int align_to_integer);

	STBTT_DEF int  stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
	STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects);
	STBTT_DEF int  stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
	// Calling these functions in sequence is roughly equivalent to calling
	// stbtt_PackFontRanges(). If you more control over the packing of multiple
	// fonts, or if you want to pack custom data into a font texture, take a look
	// at the source to of stbtt_PackFontRanges() and create a custom version 
	// using these functions, e.g. call GatherRects multiple times,
	// building up a single array of rects, then call PackRects once,
	// then call RenderIntoRects repeatedly. This may result in a
	// better packing than calling PackFontRanges multiple times
	// (or it may not).

	// this is an opaque structure that you shouldn't mess with which holds
	// all the context needed from PackBegin to PackEnd.
	struct stbtt_pack_context {
		void *user_allocator_context;
		void *pack_info;
		int   width;
		int   height;
		int   stride_in_bytes;
		int   padding;
		unsigned int   h_oversample, v_oversample;
		unsigned char *pixels;
		void  *nodes;
	};

	//////////////////////////////////////////////////////////////////////////////
	//
	// FONT LOADING
	//
	//

	STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data);
	// This function will determine the number of fonts in a font file.  TrueType
	// collection (.ttc) files may contain multiple fonts, while TrueType font
	// (.ttf) files only contain one font. The number of fonts can be used for
	// indexing with the previous function where the index is between zero and one
	// less than the total fonts. If an error occurs, -1 is returned.

	STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index);
	// Each .ttf/.ttc file may have more than one font. Each font has a sequential
	// index number starting from 0. Call this function to get the font offset for
	// a given index; it returns -1 if the index is out of range. A regular .ttf
	// file will only define one font and it always be at offset 0, so it will
	// return '0' for index 0, and -1 for all other indices.

	// The following structure is defined publically so you can declare one on
	// the stack or as a global or etc, but you should treat it as opaque.
	struct stbtt_fontinfo
	{
		void           * userdata;
		unsigned char  * data;              // pointer to .ttf file
		int              fontstart;         // offset of start of font

		int numGlyphs;                     // number of glyphs, needed for range checking

		int loca, head, glyf, hhea, hmtx, kern; // table locations as offset from start of .ttf
		int index_map;                     // a cmap mapping for our chosen character encoding
		int indexToLocFormat;              // format needed to map from glyph index to glyph

		stbtt__buf cff;                    // cff font data
		stbtt__buf charstrings;            // the charstring index
		stbtt__buf gsubrs;                 // global charstring subroutines index
		stbtt__buf subrs;                  // private charstring subroutines index
		stbtt__buf fontdicts;              // array of font dicts
		stbtt__buf fdselect;               // map from glyph to fontdict
	};

	STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset);
	// Given an offset into the file that defines a font, this function builds
	// the necessary cached info for the rest of the system. You must allocate
	// the stbtt_fontinfo yourself, and stbtt_InitFont will fill it out. You don't
	// need to do anything special to free it, because the contents are pure
	// value data with no additional data structures. Returns 0 on failure.


	//////////////////////////////////////////////////////////////////////////////
	//
	// CHARACTER TO GLYPH-INDEX CONVERSIOn

	STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint);
	// If you're going to perform multiple operations on the same character
	// and you want a speed-up, call this function with the character you're
	// going to process, then use glyph-based functions instead of the
	// codepoint-based functions.


	//////////////////////////////////////////////////////////////////////////////
	//
	// CHARACTER PROPERTIES
	//

	STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float pixels);
	// computes a scale factor to produce a font whose "height" is 'pixels' tall.
	// Height is measured as the distance from the highest ascender to the lowest
	// descender; in other words, it's equivalent to calling stbtt_GetFontVMetrics
	// and computing:
	//       scale = pixels / (ascent - descent)
	// so if you prefer to measure height by the ascent only, use a similar calculation.

	STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels);
	// computes a scale factor to produce a font whose EM size is mapped to
	// 'pixels' tall. This is probably what traditional APIs compute, but
	// I'm not positive.

	STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap);
	// ascent is the coordinate above the baseline the font extends; descent
	// is the coordinate below the baseline the font extends (i.e. it is typically negative)
	// lineGap is the spacing between one row's descent and the next row's ascent...
	// so you should advance the vertical position by "*ascent - *descent + *lineGap"
	//   these are expressed in unscaled coordinates, so you must multiply by
	//   the scale factor for a given size

	STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1);
	// the bounding box around all possible characters

	STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing);
	// leftSideBearing is the offset from the current horizontal position to the left edge of the character
	// advanceWidth is the offset from the current horizontal position to the next horizontal position
	//   these are expressed in unscaled coordinates

	STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2);
	// an additional amount to add to the 'advance' value between ch1 and ch2

	STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1);
	// Gets the bounding box of the visible part of the glyph, in unscaled coordinates

	STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing);
	STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2);
	STBTT_DEF int  stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
	// as above, but takes one or more glyph indices for greater efficiency


	//////////////////////////////////////////////////////////////////////////////
	//
	// GLYPH SHAPES (you probably don't need these, but they have to go before
	// the bitmaps for C declaration-order reasons)
	//

#ifndef STBTT_vmove // you can predefine these to use different values (but why?)
	enum {
		STBTT_vmove = 1,
		STBTT_vline,
		STBTT_vcurve,
		STBTT_vcubic
	};
#endif

#ifndef stbtt_vertex // you can predefine this to use different values
	// (we share this with other code at RAD)
#define stbtt_vertex_type short // can't use stbtt_int16 because that's not visible in the header file
	typedef struct
	{
		stbtt_vertex_type x, y, cx, cy, cx1, cy1;
		unsigned char type, padding;
	} stbtt_vertex;
#endif

	STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index);
	// returns non-zero if nothing is drawn for this glyph

	STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices);
	STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **vertices);
	// returns # of vertices and fills *vertices with the pointer to them
	//   these are expressed in "unscaled" coordinates
	//
	// The shape is a series of countours. Each one starts with
	// a STBTT_moveto, then consists of a series of mixed
	// STBTT_lineto and STBTT_curveto segments. A lineto
	// draws a line from previous endpoint to its x,y; a curveto
	// draws a quadratic bezier from previous endpoint to
	// its x,y, using cx,cy as the bezier control point.

	STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices);
	// frees the data allocated above

	//////////////////////////////////////////////////////////////////////////////
	//
	// BITMAP RENDERING
	//

	STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata);
	// frees the bitmap allocated below

	STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
	// allocates a large-enough single-channel 8bpp bitmap and renders the
	// specified character/glyph at the specified scale into it, with
	// antialiasing. 0 is no coverage (transparent), 255 is fully covered (opaque).
	// *width & *height are filled out with the width & height of the bitmap,
	// which is stored left-to-right, top-to-bottom.
	//
	// xoff/yoff are the offset it pixel space from the glyph origin to the top-left of the bitmap

	STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
	// the same as stbtt_GetCodepoitnBitmap, but you can specify a subpixel
	// shift for the character

	STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint);
	// the same as stbtt_GetCodepointBitmap, but you pass in storage for the bitmap
	// in the form of 'output', with row spacing of 'out_stride' bytes. the bitmap
	// is clipped to out_w/out_h bytes. Call stbtt_GetCodepointBitmapBox to get the
	// width and height and positioning info for it first.

	STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint);
	// same as stbtt_MakeCodepointBitmap, but you can specify a subpixel
	// shift for the character

	STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
	// get the bbox of the bitmap centered around the glyph origin; so the
	// bitmap width is ix1-ix0, height is iy1-iy0, and location to place
	// the bitmap top left is (leftSideBearing*scale,iy0).
	// (Note that the bitmap uses y-increases-down, but the shape uses
	// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)

	STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
	// same as stbtt_GetCodepointBitmapBox, but you can specify a subpixel
	// shift for the character

	// the following functions are equivalent to the above functions, but operate
	// on glyph indices instead of Unicode codepoints (for efficiency)
	STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff);
	STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff);
	STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph);
	STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph);
	STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
	STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);


	// @TODO: don't expose this structure
	typedef struct
	{
		int w, h, stride;
		unsigned char *pixels;
	} stbtt__bitmap;

	// rasterize a shape with quadratic beziers into a bitmap
	STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result,        // 1-channel bitmap to draw into
		float flatness_in_pixels,     // allowable error of curve in pixels
		stbtt_vertex *vertices,       // array of vertices defining shape
		int num_verts,                // number of vertices in above array
		float scale_x, float scale_y, // scale applied to input vertices
		float shift_x, float shift_y, // translation applied to input vertices
		int x_off, int y_off,         // another translation applied to input
		int invert,                   // if non-zero, vertically flip shape
		void *userdata);              // context for to STBTT_MALLOC

									  //////////////////////////////////////////////////////////////////////////////
									  //
									  // Finding the right font...
									  //
									  // You should really just solve this offline, keep your own tables
									  // of what font is what, and don't try to get it out of the .ttf file.
									  // That's because getting it out of the .ttf file is really hard, because
									  // the names in the file can appear in many possible encodings, in many
									  // possible languages, and e.g. if you need a case-insensitive comparison,
									  // the details of that depend on the encoding & language in a complex way
									  // (actually underspecified in truetype, but also gigantic).
									  //
									  // But you can use the provided functions in two possible ways:
									  //     stbtt_FindMatchingFont() will use *case-sensitive* comparisons on
									  //             unicode-encoded names to try to find the font you want;
									  //             you can run this before calling stbtt_InitFont()
									  //
									  //     stbtt_GetFontNameString() lets you get any of the various strings
									  //             from the file yourself and do your own comparisons on them.
									  //             You have to have called stbtt_InitFont() first.


	STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags);
	// returns the offset (not index) of the font that matches, or -1 if none
	//   if you use STBTT_MACSTYLE_DONTCARE, use a font name like "Arial Bold".
	//   if you use any other flag, use a font name like "Arial"; this checks
	//     the 'macStyle' header field; i don't know if fonts set this consistently
#define STBTT_MACSTYLE_DONTCARE     0
#define STBTT_MACSTYLE_BOLD         1
#define STBTT_MACSTYLE_ITALIC       2
#define STBTT_MACSTYLE_UNDERSCORE   4
#define STBTT_MACSTYLE_NONE         8   // <= not same as 0, this makes us check the bitfield is 0

	STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2);
	// returns 1/0 whether the first string interpreted as utf8 is identical to
	// the second string interpreted as big-endian utf16... useful for strings from next func

	STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID);
	// returns the string (which may be big-endian double byte, e.g. for unicode)
	// and puts the length in bytes in *length.
	//
	// some of the values for the IDs are below; for more see the truetype spec:
	//     http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6name.html
	//     http://www.microsoft.com/typography/otspec/name.htm

	enum { // platformID
		STBTT_PLATFORM_ID_UNICODE = 0,
		STBTT_PLATFORM_ID_MAC = 1,
		STBTT_PLATFORM_ID_ISO = 2,
		STBTT_PLATFORM_ID_MICROSOFT = 3
	};

	enum { // encodingID for STBTT_PLATFORM_ID_UNICODE
		STBTT_UNICODE_EID_UNICODE_1_0 = 0,
		STBTT_UNICODE_EID_UNICODE_1_1 = 1,
		STBTT_UNICODE_EID_ISO_10646 = 2,
		STBTT_UNICODE_EID_UNICODE_2_0_BMP = 3,
		STBTT_UNICODE_EID_UNICODE_2_0_FULL = 4
	};

	enum { // encodingID for STBTT_PLATFORM_ID_MICROSOFT
		STBTT_MS_EID_SYMBOL = 0,
		STBTT_MS_EID_UNICODE_BMP = 1,
		STBTT_MS_EID_SHIFTJIS = 2,
		STBTT_MS_EID_UNICODE_FULL = 10
	};

	enum { // encodingID for STBTT_PLATFORM_ID_MAC; same as Script Manager codes
		STBTT_MAC_EID_ROMAN = 0, STBTT_MAC_EID_ARABIC = 4,
		STBTT_MAC_EID_JAPANESE = 1, STBTT_MAC_EID_HEBREW = 5,
		STBTT_MAC_EID_CHINESE_TRAD = 2, STBTT_MAC_EID_GREEK = 6,
		STBTT_MAC_EID_KOREAN = 3, STBTT_MAC_EID_RUSSIAN = 7
	};

	enum { // languageID for STBTT_PLATFORM_ID_MICROSOFT; same as LCID...
		   // problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs
		STBTT_MS_LANG_ENGLISH = 0x0409, STBTT_MS_LANG_ITALIAN = 0x0410,
		STBTT_MS_LANG_CHINESE = 0x0804, STBTT_MS_LANG_JAPANESE = 0x0411,
		STBTT_MS_LANG_DUTCH = 0x0413, STBTT_MS_LANG_KOREAN = 0x0412,
		STBTT_MS_LANG_FRENCH = 0x040c, STBTT_MS_LANG_RUSSIAN = 0x0419,
		STBTT_MS_LANG_GERMAN = 0x0407, STBTT_MS_LANG_SPANISH = 0x0409,
		STBTT_MS_LANG_HEBREW = 0x040d, STBTT_MS_LANG_SWEDISH = 0x041D
	};

	enum { // languageID for STBTT_PLATFORM_ID_MAC
		STBTT_MAC_LANG_ENGLISH = 0, STBTT_MAC_LANG_JAPANESE = 11,
		STBTT_MAC_LANG_ARABIC = 12, STBTT_MAC_LANG_KOREAN = 23,
		STBTT_MAC_LANG_DUTCH = 4, STBTT_MAC_LANG_RUSSIAN = 32,
		STBTT_MAC_LANG_FRENCH = 1, STBTT_MAC_LANG_SPANISH = 6,
		STBTT_MAC_LANG_GERMAN = 2, STBTT_MAC_LANG_SWEDISH = 5,
		STBTT_MAC_LANG_HEBREW = 10, STBTT_MAC_LANG_CHINESE_SIMPLIFIED = 33,
		STBTT_MAC_LANG_ITALIAN = 3, STBTT_MAC_LANG_CHINESE_TRAD = 19
	};

#ifdef __cplusplus
}
#endif

#endif // __STB_INCLUDE_STB_TRUETYPE_H__

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
////
////   IMPLEMENTATION
////
////

#ifdef STB_TRUETYPE_IMPLEMENTATION

#ifndef STBTT_MAX_OVERSAMPLE
#define STBTT_MAX_OVERSAMPLE   8
#endif

#if STBTT_MAX_OVERSAMPLE > 255
//#error "STBTT_MAX_OVERSAMPLE cannot be > 255"
#endif

typedef int stbtt__test_oversample_pow2[(STBTT_MAX_OVERSAMPLE & (STBTT_MAX_OVERSAMPLE - 1)) == 0 ? 1 : -1];

#ifndef STBTT_RASTERIZER_VERSION
#define STBTT_RASTERIZER_VERSION 2
#endif

#ifdef _MSC_VER
#define STBTT__NOTUSED(v)  (void)(v)
#else
#define STBTT__NOTUSED(v)  (void)sizeof(v)
#endif

//////////////////////////////////////////////////////////////////////////
//
// stbtt__buf helpers to parse data from file
//

static stbtt_uint8 stbtt__buf_get8(stbtt__buf *b)
{
	if (b->cursor >= b->size)
		return 0;
	return b->data[b->cursor++];
}

static stbtt_uint8 stbtt__buf_peek8(stbtt__buf *b)
{
	if (b->cursor >= b->size)
		return 0;
	return b->data[b->cursor];
}

static void stbtt__buf_seek(stbtt__buf *b, int o)
{
	STBTT_assert(!(o > b->size || o < 0));
	b->cursor = (o > b->size || o < 0) ? b->size : o;
}

static void stbtt__buf_skip(stbtt__buf *b, int o)
{
	stbtt__buf_seek(b, b->cursor + o);
}

static stbtt_uint32 stbtt__buf_get(stbtt__buf *b, int n)
{
	stbtt_uint32 v = 0;
	int i;
	STBTT_assert(n >= 1 && n <= 4);
	for (i = 0; i < n; i++)
		v = (v << 8) | stbtt__buf_get8(b);
	return v;
}

static stbtt__buf stbtt__new_buf(const void *p, size_t size)
{
	stbtt__buf r;
	STBTT_assert(size < 0x40000000);
	r.data = (stbtt_uint8*)p;
	r.size = (int)size;
	r.cursor = 0;
	return r;
}

#define stbtt__buf_get16(b)  stbtt__buf_get((b), 2)
#define stbtt__buf_get32(b)  stbtt__buf_get((b), 4)

static stbtt__buf stbtt__buf_range(const stbtt__buf *b, int o, int s)
{
	stbtt__buf r = stbtt__new_buf(NULL, 0);
	if (o < 0 || s < 0 || o > b->size || s > b->size - o) return r;
	r.data = b->data + o;
	r.size = s;
	return r;
}

static stbtt__buf stbtt__cff_get_index(stbtt__buf *b)
{
	int count, start, offsize;
	start = b->cursor;
	count = stbtt__buf_get16(b);
	if (count) {
		offsize = stbtt__buf_get8(b);
		STBTT_assert(offsize >= 1 && offsize <= 4);
		stbtt__buf_skip(b, offsize * count);
		stbtt__buf_skip(b, stbtt__buf_get(b, offsize) - 1);
	}
	return stbtt__buf_range(b, start, b->cursor - start);
}

static stbtt_uint32 stbtt__cff_int(stbtt__buf *b)
{
	int b0 = stbtt__buf_get8(b);
	if (b0 >= 32 && b0 <= 246)       return b0 - 139;
	else if (b0 >= 247 && b0 <= 250) return (b0 - 247) * 256 + stbtt__buf_get8(b) + 108;
	else if (b0 >= 251 && b0 <= 254) return -(b0 - 251) * 256 - stbtt__buf_get8(b) - 108;
	else if (b0 == 28)               return stbtt__buf_get16(b);
	else if (b0 == 29)               return stbtt__buf_get32(b);
	STBTT_assert(0);
	return 0;
}

static void stbtt__cff_skip_operand(stbtt__buf *b) {
	int v, b0 = stbtt__buf_peek8(b);
	STBTT_assert(b0 >= 28);
	if (b0 == 30) {
		stbtt__buf_skip(b, 1);
		while (b->cursor < b->size) {
			v = stbtt__buf_get8(b);
			if ((v & 0xF) == 0xF || (v >> 4) == 0xF)
				break;
		}
	}
	else {
		stbtt__cff_int(b);
	}
}

static stbtt__buf stbtt__dict_get(stbtt__buf *b, int key)
{
	stbtt__buf_seek(b, 0);
	while (b->cursor < b->size) {
		int start = b->cursor, end, op;
		while (stbtt__buf_peek8(b) >= 28)
			stbtt__cff_skip_operand(b);
		end = b->cursor;
		op = stbtt__buf_get8(b);
		if (op == 12)  op = stbtt__buf_get8(b) | 0x100;
		if (op == key) return stbtt__buf_range(b, start, end - start);
	}
	return stbtt__buf_range(b, 0, 0);
}

static void stbtt__dict_get_ints(stbtt__buf *b, int key, int outcount, stbtt_uint32 *out)
{
	int i;
	stbtt__buf operands = stbtt__dict_get(b, key);
	for (i = 0; i < outcount && operands.cursor < operands.size; i++)
		out[i] = stbtt__cff_int(&operands);
}

static int stbtt__cff_index_count(stbtt__buf *b)
{
	stbtt__buf_seek(b, 0);
	return stbtt__buf_get16(b);
}

static stbtt__buf stbtt__cff_index_get(stbtt__buf b, int i)
{
	int count, offsize, start, end;
	stbtt__buf_seek(&b, 0);
	count = stbtt__buf_get16(&b);
	offsize = stbtt__buf_get8(&b);
	STBTT_assert(i >= 0 && i < count);
	STBTT_assert(offsize >= 1 && offsize <= 4);
	stbtt__buf_skip(&b, i*offsize);
	start = stbtt__buf_get(&b, offsize);
	end = stbtt__buf_get(&b, offsize);
	return stbtt__buf_range(&b, 2 + (count + 1)*offsize + start, end - start);
}

//////////////////////////////////////////////////////////////////////////
//
// accessors to parse data from file
//

// on platforms that don't allow misaligned reads, if we want to allow
// truetype fonts that aren't padded to alignment, define ALLOW_UNALIGNED_TRUETYPE

#define ttBYTE(p)     (* (stbtt_uint8 *) (p))
#define ttCHAR(p)     (* (stbtt_int8 *) (p))
#define ttFixed(p)    ttLONG(p)

static stbtt_uint16 ttUSHORT(stbtt_uint8 *p) { return p[0] * 256 + p[1]; }
static stbtt_int16 ttSHORT(stbtt_uint8 *p) { return p[0] * 256 + p[1]; }
static stbtt_uint32 ttULONG(stbtt_uint8 *p) { return (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; }
static stbtt_int32 ttLONG(stbtt_uint8 *p) { return (p[0] << 24) + (p[1] << 16) + (p[2] << 8) + p[3]; }

#define stbtt_tag4(p,c0,c1,c2,c3) ((p)[0] == (c0) && (p)[1] == (c1) && (p)[2] == (c2) && (p)[3] == (c3))
#define stbtt_tag(p,str)           stbtt_tag4(p,str[0],str[1],str[2],str[3])

static int stbtt__isfont(stbtt_uint8 *font)
{
	// check the version number
	if (stbtt_tag4(font, '1', 0, 0, 0))  return 1; // TrueType 1
	if (stbtt_tag(font, "typ1"))   return 1; // TrueType with type 1 font -- we don't support this!
	if (stbtt_tag(font, "OTTO"))   return 1; // OpenType with CFF
	if (stbtt_tag4(font, 0, 1, 0, 0)) return 1; // OpenType 1.0
	if (stbtt_tag(font, "true"))   return 1; // Apple specification for TrueType fonts
	return 0;
}

// @OPTIMIZE: binary search
static stbtt_uint32 stbtt__find_table(stbtt_uint8 *data, stbtt_uint32 fontstart, const char *tag)
{
	stbtt_int32 num_tables = ttUSHORT(data + fontstart + 4);
	stbtt_uint32 tabledir = fontstart + 12;
	stbtt_int32 i;
	for (i = 0; i < num_tables; ++i) {
		stbtt_uint32 loc = tabledir + 16 * i;
		if (stbtt_tag(data + loc + 0, tag))
			return ttULONG(data + loc + 8);
	}
	return 0;
}

static int stbtt_GetFontOffsetForIndex_internal(unsigned char *font_collection, int index)
{
	// if it's just a font, there's only one valid index
	if (stbtt__isfont(font_collection))
		return index == 0 ? 0 : -1;

	// check if it's a TTC
	if (stbtt_tag(font_collection, "ttcf")) {
		// version 1?
		if (ttULONG(font_collection + 4) == 0x00010000 || ttULONG(font_collection + 4) == 0x00020000) {
			stbtt_int32 n = ttLONG(font_collection + 8);
			if (index >= n)
				return -1;
			return ttULONG(font_collection + 12 + index * 4);
		}
	}
	return -1;
}

static int stbtt_GetNumberOfFonts_internal(unsigned char *font_collection)
{
	// if it's just a font, there's only one valid font
	if (stbtt__isfont(font_collection))
		return 1;

	// check if it's a TTC
	if (stbtt_tag(font_collection, "ttcf")) {
		// version 1?
		if (ttULONG(font_collection + 4) == 0x00010000 || ttULONG(font_collection + 4) == 0x00020000) {
			return ttLONG(font_collection + 8);
		}
	}
	return 0;
}

static stbtt__buf stbtt__get_subrs(stbtt__buf cff, stbtt__buf fontdict)
{
	stbtt_uint32 subrsoff = 0, private_loc[2] = { 0, 0 };
	stbtt__buf pdict;
	stbtt__dict_get_ints(&fontdict, 18, 2, private_loc);
	if (!private_loc[1] || !private_loc[0]) return stbtt__new_buf(NULL, 0);
	pdict = stbtt__buf_range(&cff, private_loc[1], private_loc[0]);
	stbtt__dict_get_ints(&pdict, 19, 1, &subrsoff);
	if (!subrsoff) return stbtt__new_buf(NULL, 0);
	stbtt__buf_seek(&cff, private_loc[1] + subrsoff);
	return stbtt__cff_get_index(&cff);
}

static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart)
{
	stbtt_uint32 cmap, t;
	stbtt_int32 i, numTables;

	info->data = data;
	info->fontstart = fontstart;
	info->cff = stbtt__new_buf(NULL, 0);

	cmap = stbtt__find_table(data, fontstart, "cmap");       // required
	info->loca = stbtt__find_table(data, fontstart, "loca"); // required
	info->head = stbtt__find_table(data, fontstart, "head"); // required
	info->glyf = stbtt__find_table(data, fontstart, "glyf"); // required
	info->hhea = stbtt__find_table(data, fontstart, "hhea"); // required
	info->hmtx = stbtt__find_table(data, fontstart, "hmtx"); // required
	info->kern = stbtt__find_table(data, fontstart, "kern"); // not required

	if (!cmap || !info->head || !info->hhea || !info->hmtx)
		return 0;
	if (info->glyf) {
		// required for truetype
		if (!info->loca) return 0;
	}
	else {
		// initialization for CFF / Type2 fonts (OTF)
		stbtt__buf b, topdict, topdictidx;
		stbtt_uint32 cstype = 2, charstrings = 0, fdarrayoff = 0, fdselectoff = 0;
		stbtt_uint32 cff;

		cff = stbtt__find_table(data, fontstart, "CFF ");
		if (!cff) return 0;

		info->fontdicts = stbtt__new_buf(NULL, 0);
		info->fdselect = stbtt__new_buf(NULL, 0);

		// @TODO this should use size from table (not 512MB)
		info->cff = stbtt__new_buf(data + cff, 512 * 1024 * 1024);
		b = info->cff;

		// read the header
		stbtt__buf_skip(&b, 2);
		stbtt__buf_seek(&b, stbtt__buf_get8(&b)); // hdrsize

												  // @TODO the name INDEX could list multiple fonts,
												  // but we just use the first one.
		stbtt__cff_get_index(&b);  // name INDEX
		topdictidx = stbtt__cff_get_index(&b);
		topdict = stbtt__cff_index_get(topdictidx, 0);
		stbtt__cff_get_index(&b);  // string INDEX
		info->gsubrs = stbtt__cff_get_index(&b);

		stbtt__dict_get_ints(&topdict, 17, 1, &charstrings);
		stbtt__dict_get_ints(&topdict, 0x100 | 6, 1, &cstype);
		stbtt__dict_get_ints(&topdict, 0x100 | 36, 1, &fdarrayoff);
		stbtt__dict_get_ints(&topdict, 0x100 | 37, 1, &fdselectoff);
		info->subrs = stbtt__get_subrs(b, topdict);

		// we only support Type 2 charstrings
		if (cstype != 2) return 0;
		if (charstrings == 0) return 0;

		if (fdarrayoff) {
			// looks like a CID font
			if (!fdselectoff) return 0;
			stbtt__buf_seek(&b, fdarrayoff);
			info->fontdicts = stbtt__cff_get_index(&b);
			info->fdselect = stbtt__buf_range(&b, fdselectoff, b.size - fdselectoff);
		}

		stbtt__buf_seek(&b, charstrings);
		info->charstrings = stbtt__cff_get_index(&b);
	}

	t = stbtt__find_table(data, fontstart, "maxp");
	if (t)
		info->numGlyphs = ttUSHORT(data + t + 4);
	else
		info->numGlyphs = 0xffff;

	// find a cmap encoding table we understand *now* to avoid searching
	// later. (todo: could make this installable)
	// the same regardless of glyph.
	numTables = ttUSHORT(data + cmap + 2);
	info->index_map = 0;
	for (i = 0; i < numTables; ++i) {
		stbtt_uint32 encoding_record = cmap + 4 + 8 * i;
		// find an encoding we understand:
		switch (ttUSHORT(data + encoding_record)) {
		case STBTT_PLATFORM_ID_MICROSOFT:
			switch (ttUSHORT(data + encoding_record + 2)) {
			case STBTT_MS_EID_UNICODE_BMP:
			case STBTT_MS_EID_UNICODE_FULL:
				// MS/Unicode
				info->index_map = cmap + ttULONG(data + encoding_record + 4);
				break;
			}
			break;
		case STBTT_PLATFORM_ID_UNICODE:
			// Mac/iOS has these
			// all the encodingIDs are unicode, so we don't bother to check it
			info->index_map = cmap + ttULONG(data + encoding_record + 4);
			break;
		}
	}
	if (info->index_map == 0)
		return 0;

	info->indexToLocFormat = ttUSHORT(data + info->head + 50);
	return 1;
}

STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint)
{
	stbtt_uint8 *data = info->data;
	stbtt_uint32 index_map = info->index_map;

	stbtt_uint16 format = ttUSHORT(data + index_map + 0);
	if (format == 0) { // apple byte encoding
		stbtt_int32 bytes = ttUSHORT(data + index_map + 2);
		if (unicode_codepoint < bytes - 6)
			return ttBYTE(data + index_map + 6 + unicode_codepoint);
		return 0;
	}
	else if (format == 6) {
		stbtt_uint32 first = ttUSHORT(data + index_map + 6);
		stbtt_uint32 count = ttUSHORT(data + index_map + 8);
		if ((stbtt_uint32)unicode_codepoint >= first && (stbtt_uint32)unicode_codepoint < first + count)
			return ttUSHORT(data + index_map + 10 + (unicode_codepoint - first) * 2);
		return 0;
	}
	else if (format == 2) {
		STBTT_assert(0); // @TODO: high-byte mapping for japanese/chinese/korean
		return 0;
	}
	else if (format == 4) { // standard mapping for windows fonts: binary search collection of ranges
		stbtt_uint16 segcount = ttUSHORT(data + index_map + 6) >> 1;
		stbtt_uint16 searchRange = ttUSHORT(data + index_map + 8) >> 1;
		stbtt_uint16 entrySelector = ttUSHORT(data + index_map + 10);
		stbtt_uint16 rangeShift = ttUSHORT(data + index_map + 12) >> 1;

		// do a binary search of the segments
		stbtt_uint32 endCount = index_map + 14;
		stbtt_uint32 search = endCount;

		if (unicode_codepoint > 0xffff)
			return 0;

		// they lie from endCount .. endCount + segCount
		// but searchRange is the nearest power of two, so...
		if (unicode_codepoint >= ttUSHORT(data + search + rangeShift * 2))
			search += rangeShift * 2;

		// now decrement to bias correctly to find smallest
		search -= 2;
		while (entrySelector) {
			stbtt_uint16 end;
			searchRange >>= 1;
			end = ttUSHORT(data + search + searchRange * 2);
			if (unicode_codepoint > end)
				search += searchRange * 2;
			--entrySelector;
		}
		search += 2;

		{
			stbtt_uint16 offset, start;
			stbtt_uint16 item = (stbtt_uint16)((search - endCount) >> 1);

			STBTT_assert(unicode_codepoint <= ttUSHORT(data + endCount + 2 * item));
			start = ttUSHORT(data + index_map + 14 + segcount * 2 + 2 + 2 * item);
			if (unicode_codepoint < start)
				return 0;

			offset = ttUSHORT(data + index_map + 14 + segcount * 6 + 2 + 2 * item);
			if (offset == 0)
				return (stbtt_uint16)(unicode_codepoint + ttSHORT(data + index_map + 14 + segcount * 4 + 2 + 2 * item));

			return ttUSHORT(data + offset + (unicode_codepoint - start) * 2 + index_map + 14 + segcount * 6 + 2 + 2 * item);
		}
	}
	else if (format == 12 || format == 13) {
		stbtt_uint32 ngroups = ttULONG(data + index_map + 12);
		stbtt_int32 low, high;
		low = 0; high = (stbtt_int32)ngroups;
		// Binary search the right group.
		while (low < high) {
			stbtt_int32 mid = low + ((high - low) >> 1); // rounds down, so low <= mid < high
			stbtt_uint32 start_char = ttULONG(data + index_map + 16 + mid * 12);
			stbtt_uint32 end_char = ttULONG(data + index_map + 16 + mid * 12 + 4);
			if ((stbtt_uint32)unicode_codepoint < start_char)
				high = mid;
			else if ((stbtt_uint32)unicode_codepoint > end_char)
				low = mid + 1;
			else {
				stbtt_uint32 start_glyph = ttULONG(data + index_map + 16 + mid * 12 + 8);
				if (format == 12)
					return start_glyph + unicode_codepoint - start_char;
				else // format == 13
					return start_glyph;
			}
		}
		return 0; // not found
	}
	// @TODO
	STBTT_assert(0);
	return 0;
}

STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices)
{
	return stbtt_GetGlyphShape(info, stbtt_FindGlyphIndex(info, unicode_codepoint), vertices);
}

static void stbtt_setvertex(stbtt_vertex *v, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy)
{
	v->type = type;
	v->x = (stbtt_int16)x;
	v->y = (stbtt_int16)y;
	v->cx = (stbtt_int16)cx;
	v->cy = (stbtt_int16)cy;
}

static int stbtt__GetGlyfOffset(const stbtt_fontinfo *info, int glyph_index)
{
	int g1, g2;

	STBTT_assert(!info->cff.size);

	if (glyph_index >= info->numGlyphs) return -1; // glyph index out of range
	if (info->indexToLocFormat >= 2)    return -1; // unknown index->glyph map format

	if (info->indexToLocFormat == 0) {
		g1 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2) * 2;
		g2 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2 + 2) * 2;
	}
	else {
		g1 = info->glyf + ttULONG(info->data + info->loca + glyph_index * 4);
		g2 = info->glyf + ttULONG(info->data + info->loca + glyph_index * 4 + 4);
	}

	return g1 == g2 ? -1 : g1; // if length is 0, return -1
}

static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);

STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
{
	if (info->cff.size) {
		stbtt__GetGlyphInfoT2(info, glyph_index, x0, y0, x1, y1);
	}
	else {
		int g = stbtt__GetGlyfOffset(info, glyph_index);
		if (g < 0) return 0;

		if (x0) *x0 = ttSHORT(info->data + g + 2);
		if (y0) *y0 = ttSHORT(info->data + g + 4);
		if (x1) *x1 = ttSHORT(info->data + g + 6);
		if (y1) *y1 = ttSHORT(info->data + g + 8);
	}
	return 1;
}

STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1)
{
	return stbtt_GetGlyphBox(info, stbtt_FindGlyphIndex(info, codepoint), x0, y0, x1, y1);
}

STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index)
{
	stbtt_int16 numberOfContours;
	int g;
	if (info->cff.size)
		return stbtt__GetGlyphInfoT2(info, glyph_index, NULL, NULL, NULL, NULL) == 0;
	g = stbtt__GetGlyfOffset(info, glyph_index);
	if (g < 0) return 1;
	numberOfContours = ttSHORT(info->data + g);
	return numberOfContours == 0;
}

static int stbtt__close_shape(stbtt_vertex *vertices, int num_vertices, int was_off, int start_off,
	stbtt_int32 sx, stbtt_int32 sy, stbtt_int32 scx, stbtt_int32 scy, stbtt_int32 cx, stbtt_int32 cy)
{
	if (start_off) {
		if (was_off)
			stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx + scx) >> 1, (cy + scy) >> 1, cx, cy);
		stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, sx, sy, scx, scy);
	}
	else {
		if (was_off)
			stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, sx, sy, cx, cy);
		else
			stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, sx, sy, 0, 0);
	}
	return num_vertices;
}

static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
{
	stbtt_int16 numberOfContours;
	stbtt_uint8 *endPtsOfContours;
	stbtt_uint8 *data = info->data;
	stbtt_vertex *vertices = 0;
	int num_vertices = 0;
	int g = stbtt__GetGlyfOffset(info, glyph_index);

	*pvertices = NULL;

	if (g < 0) return 0;

	numberOfContours = ttSHORT(data + g);

	if (numberOfContours > 0) {
		stbtt_uint8 flags = 0, flagcount;
		stbtt_int32 ins, i, j = 0, m, n, next_move, was_off = 0, off, start_off = 0;
		stbtt_int32 x, y, cx, cy, sx, sy, scx, scy;
		stbtt_uint8 *points;
		endPtsOfContours = (data + g + 10);
		ins = ttUSHORT(data + g + 10 + numberOfContours * 2);
		points = data + g + 10 + numberOfContours * 2 + 2 + ins;

		n = 1 + ttUSHORT(endPtsOfContours + numberOfContours * 2 - 2);

		m = n + 2 * numberOfContours;  // a loose bound on how many vertices we might need
		vertices = (stbtt_vertex *)STBTT_malloc(m * sizeof(vertices[0]), info->userdata);
		if (vertices == 0)
			return 0;

		next_move = 0;
		flagcount = 0;

		// in first pass, we load uninterpreted data into the allocated array
		// above, shifted to the end of the array so we won't overwrite it when
		// we create our final data starting from the front

		off = m - n; // starting offset for uninterpreted data, regardless of how m ends up being calculated

					 // first load flags

		for (i = 0; i < n; ++i) {
			if (flagcount == 0) {
				flags = *points++;
				if (flags & 8)
					flagcount = *points++;
			}
			else
				--flagcount;
			vertices[off + i].type = flags;
		}

		// now load x coordinates
		x = 0;
		for (i = 0; i < n; ++i) {
			flags = vertices[off + i].type;
			if (flags & 2) {
				stbtt_int16 dx = *points++;
				x += (flags & 16) ? dx : -dx; // ???
			}
			else {
				if (!(flags & 16)) {
					x = x + (stbtt_int16)(points[0] * 256 + points[1]);
					points += 2;
				}
			}
			vertices[off + i].x = (stbtt_int16)x;
		}

		// now load y coordinates
		y = 0;
		for (i = 0; i < n; ++i) {
			flags = vertices[off + i].type;
			if (flags & 4) {
				stbtt_int16 dy = *points++;
				y += (flags & 32) ? dy : -dy; // ???
			}
			else {
				if (!(flags & 32)) {
					y = y + (stbtt_int16)(points[0] * 256 + points[1]);
					points += 2;
				}
			}
			vertices[off + i].y = (stbtt_int16)y;
		}

		// now convert them to our format
		num_vertices = 0;
		sx = sy = cx = cy = scx = scy = 0;
		for (i = 0; i < n; ++i) {
			flags = vertices[off + i].type;
			x = (stbtt_int16)vertices[off + i].x;
			y = (stbtt_int16)vertices[off + i].y;

			if (next_move == i) {
				if (i != 0)
					num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx, sy, scx, scy, cx, cy);

				// now start the new one               
				start_off = !(flags & 1);
				if (start_off) {
					// if we start off with an off-curve point, then when we need to find a point on the curve
					// where we can start, and we need to save some state for when we wraparound.
					scx = x;
					scy = y;
					if (!(vertices[off + i + 1].type & 1)) {
						// next point is also a curve point, so interpolate an on-point curve
						sx = (x + (stbtt_int32)vertices[off + i + 1].x) >> 1;
						sy = (y + (stbtt_int32)vertices[off + i + 1].y) >> 1;
					}
					else {
						// otherwise just use the next point as our start point
						sx = (stbtt_int32)vertices[off + i + 1].x;
						sy = (stbtt_int32)vertices[off + i + 1].y;
						++i; // we're using point i+1 as the starting point, so skip it
					}
				}
				else {
					sx = x;
					sy = y;
				}
				stbtt_setvertex(&vertices[num_vertices++], STBTT_vmove, sx, sy, 0, 0);
				was_off = 0;
				next_move = 1 + ttUSHORT(endPtsOfContours + j * 2);
				++j;
			}
			else {
				if (!(flags & 1)) { // if it's a curve
					if (was_off) // two off-curve control points in a row means interpolate an on-curve midpoint
						stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx + x) >> 1, (cy + y) >> 1, cx, cy);
					cx = x;
					cy = y;
					was_off = 1;
				}
				else {
					if (was_off)
						stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, x, y, cx, cy);
					else
						stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, x, y, 0, 0);
					was_off = 0;
				}
			}
		}
		num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx, sy, scx, scy, cx, cy);
	}
	else if (numberOfContours == -1) {
		// Compound shapes.
		int more = 1;
		stbtt_uint8 *comp = data + g + 10;
		num_vertices = 0;
		vertices = 0;
		while (more) {
			stbtt_uint16 flags, gidx;
			int comp_num_verts = 0, i;
			stbtt_vertex *comp_verts = 0, *tmp = 0;
			float mtx[6] = { 1,0,0,1,0,0 }, m, n;

			flags = ttSHORT(comp); comp += 2;
			gidx = ttSHORT(comp); comp += 2;

			if (flags & 2) { // XY values
				if (flags & 1) { // shorts
					mtx[4] = ttSHORT(comp); comp += 2;
					mtx[5] = ttSHORT(comp); comp += 2;
				}
				else {
					mtx[4] = ttCHAR(comp); comp += 1;
					mtx[5] = ttCHAR(comp); comp += 1;
				}
			}
			else {
				// @TODO handle matching point
				STBTT_assert(0);
			}
			if (flags & (1 << 3)) { // WE_HAVE_A_SCALE
				mtx[0] = mtx[3] = ttSHORT(comp) / 16384.0f; comp += 2;
				mtx[1] = mtx[2] = 0;
			}
			else if (flags & (1 << 6)) { // WE_HAVE_AN_X_AND_YSCALE
				mtx[0] = ttSHORT(comp) / 16384.0f; comp += 2;
				mtx[1] = mtx[2] = 0;
				mtx[3] = ttSHORT(comp) / 16384.0f; comp += 2;
			}
			else if (flags & (1 << 7)) { // WE_HAVE_A_TWO_BY_TWO
				mtx[0] = ttSHORT(comp) / 16384.0f; comp += 2;
				mtx[1] = ttSHORT(comp) / 16384.0f; comp += 2;
				mtx[2] = ttSHORT(comp) / 16384.0f; comp += 2;
				mtx[3] = ttSHORT(comp) / 16384.0f; comp += 2;
			}

			// Find transformation scales.
			m = (float)STBTT_sqrt(mtx[0] * mtx[0] + mtx[1] * mtx[1]);
			n = (float)STBTT_sqrt(mtx[2] * mtx[2] + mtx[3] * mtx[3]);

			// Get indexed glyph.
			comp_num_verts = stbtt_GetGlyphShape(info, gidx, &comp_verts);
			if (comp_num_verts > 0) {
				// Transform vertices.
				for (i = 0; i < comp_num_verts; ++i) {
					stbtt_vertex* v = &comp_verts[i];
					stbtt_vertex_type x, y;
					x = v->x; y = v->y;
					v->x = (stbtt_vertex_type)(m * (mtx[0] * x + mtx[2] * y + mtx[4]));
					v->y = (stbtt_vertex_type)(n * (mtx[1] * x + mtx[3] * y + mtx[5]));
					x = v->cx; y = v->cy;
					v->cx = (stbtt_vertex_type)(m * (mtx[0] * x + mtx[2] * y + mtx[4]));
					v->cy = (stbtt_vertex_type)(n * (mtx[1] * x + mtx[3] * y + mtx[5]));
				}
				// Append vertices.
				tmp = (stbtt_vertex*)STBTT_malloc((num_vertices + comp_num_verts) * sizeof(stbtt_vertex), info->userdata);
				if (!tmp) {
					if (vertices) STBTT_free(vertices, info->userdata);
					if (comp_verts) STBTT_free(comp_verts, info->userdata);
					return 0;
				}
				if (num_vertices > 0) STBTT_memcpy(tmp, vertices, num_vertices * sizeof(stbtt_vertex));
				STBTT_memcpy(tmp + num_vertices, comp_verts, comp_num_verts * sizeof(stbtt_vertex));
				if (vertices) STBTT_free(vertices, info->userdata);
				vertices = tmp;
				STBTT_free(comp_verts, info->userdata);
				num_vertices += comp_num_verts;
			}
			// More components ?
			more = flags & (1 << 5);
		}
	}
	else if (numberOfContours < 0) {
		// @TODO other compound variations?
		STBTT_assert(0);
	}
	else {
		// numberOfCounters == 0, do nothing
	}

	*pvertices = vertices;
	return num_vertices;
}

typedef struct
{
	int bounds;
	int started;
	float first_x, first_y;
	float x, y;
	stbtt_int32 min_x, max_x, min_y, max_y;

	stbtt_vertex *pvertices;
	int num_vertices;
} stbtt__csctx;

#define STBTT__CSCTX_INIT(bounds) {bounds,0, 0,0, 0,0, 0,0,0,0, NULL, 0}

static void stbtt__track_vertex(stbtt__csctx *c, stbtt_int32 x, stbtt_int32 y)
{
	if (x > c->max_x || !c->started) c->max_x = x;
	if (y > c->max_y || !c->started) c->max_y = y;
	if (x < c->min_x || !c->started) c->min_x = x;
	if (y < c->min_y || !c->started) c->min_y = y;
	c->started = 1;
}

static void stbtt__csctx_v(stbtt__csctx *c, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy, stbtt_int32 cx1, stbtt_int32 cy1)
{
	if (c->bounds) {
		stbtt__track_vertex(c, x, y);
		if (type == STBTT_vcubic) {
			stbtt__track_vertex(c, cx, cy);
			stbtt__track_vertex(c, cx1, cy1);
		}
	}
	else {
		stbtt_setvertex(&c->pvertices[c->num_vertices], type, x, y, cx, cy);
		c->pvertices[c->num_vertices].cx1 = (stbtt_int16)cx1;
		c->pvertices[c->num_vertices].cy1 = (stbtt_int16)cy1;
	}
	c->num_vertices++;
}

static void stbtt__csctx_close_shape(stbtt__csctx *ctx)
{
	if (ctx->first_x != ctx->x || ctx->first_y != ctx->y)
		stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->first_x, (int)ctx->first_y, 0, 0, 0, 0);
}

static void stbtt__csctx_rmove_to(stbtt__csctx *ctx, float dx, float dy)
{
	stbtt__csctx_close_shape(ctx);
	ctx->first_x = ctx->x = ctx->x + dx;
	ctx->first_y = ctx->y = ctx->y + dy;
	stbtt__csctx_v(ctx, STBTT_vmove, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0);
}

static void stbtt__csctx_rline_to(stbtt__csctx *ctx, float dx, float dy)
{
	ctx->x += dx;
	ctx->y += dy;
	stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0);
}

static void stbtt__csctx_rccurve_to(stbtt__csctx *ctx, float dx1, float dy1, float dx2, float dy2, float dx3, float dy3)
{
	float cx1 = ctx->x + dx1;
	float cy1 = ctx->y + dy1;
	float cx2 = cx1 + dx2;
	float cy2 = cy1 + dy2;
	ctx->x = cx2 + dx3;
	ctx->y = cy2 + dy3;
	stbtt__csctx_v(ctx, STBTT_vcubic, (int)ctx->x, (int)ctx->y, (int)cx1, (int)cy1, (int)cx2, (int)cy2);
}

static stbtt__buf stbtt__get_subr(stbtt__buf idx, int n)
{
	int count = stbtt__cff_index_count(&idx);
	int bias = 107;
	if (count >= 33900)
		bias = 32768;
	else if (count >= 1240)
		bias = 1131;
	n += bias;
	if (n < 0 || n >= count)
		return stbtt__new_buf(NULL, 0);
	return stbtt__cff_index_get(idx, n);
}

static stbtt__buf stbtt__cid_get_glyph_subrs(const stbtt_fontinfo *info, int glyph_index)
{
	stbtt__buf fdselect = info->fdselect;
	int nranges, start, end, v, fmt, fdselector = -1, i;

	stbtt__buf_seek(&fdselect, 0);
	fmt = stbtt__buf_get8(&fdselect);
	if (fmt == 0) {
		// untested
		stbtt__buf_skip(&fdselect, glyph_index);
		fdselector = stbtt__buf_get8(&fdselect);
	}
	else if (fmt == 3) {
		nranges = stbtt__buf_get16(&fdselect);
		start = stbtt__buf_get16(&fdselect);
		for (i = 0; i < nranges; i++) {
			v = stbtt__buf_get8(&fdselect);
			end = stbtt__buf_get16(&fdselect);
			if (glyph_index >= start && glyph_index < end) {
				fdselector = v;
				break;
			}
			start = end;
		}
	}
	if (fdselector == -1) stbtt__new_buf(NULL, 0);
	return stbtt__get_subrs(info->cff, stbtt__cff_index_get(info->fontdicts, fdselector));
}

static int stbtt__run_charstring(const stbtt_fontinfo *info, int glyph_index, stbtt__csctx *c)
{
	int in_header = 1, maskbits = 0, subr_stack_height = 0, sp = 0, v, i, b0;
	int has_subrs = 0, clear_stack;
	float s[48];
	stbtt__buf subr_stack[10], subrs = info->subrs, b;
	float f;

#define STBTT__CSERR(s) (0)

	// this currently ignores the initial width value, which isn't needed if we have hmtx
	b = stbtt__cff_index_get(info->charstrings, glyph_index);
	while (b.cursor < b.size) {
		i = 0;
		clear_stack = 1;
		b0 = stbtt__buf_get8(&b);
		switch (b0) {
			// @TODO implement hinting
		case 0x13: // hintmask
		case 0x14: // cntrmask
			if (in_header)
				maskbits += (sp / 2); // implicit "vstem"
			in_header = 0;
			stbtt__buf_skip(&b, (maskbits + 7) / 8);
			break;

		case 0x01: // hstem
		case 0x03: // vstem
		case 0x12: // hstemhm
		case 0x17: // vstemhm
			maskbits += (sp / 2);
			break;

		case 0x15: // rmoveto
			in_header = 0;
			if (sp < 2) return STBTT__CSERR("rmoveto stack");
			stbtt__csctx_rmove_to(c, s[sp - 2], s[sp - 1]);
			break;
		case 0x04: // vmoveto
			in_header = 0;
			if (sp < 1) return STBTT__CSERR("vmoveto stack");
			stbtt__csctx_rmove_to(c, 0, s[sp - 1]);
			break;
		case 0x16: // hmoveto
			in_header = 0;
			if (sp < 1) return STBTT__CSERR("hmoveto stack");
			stbtt__csctx_rmove_to(c, s[sp - 1], 0);
			break;

		case 0x05: // rlineto
			if (sp < 2) return STBTT__CSERR("rlineto stack");
			for (; i + 1 < sp; i += 2)
				stbtt__csctx_rline_to(c, s[i], s[i + 1]);
			break;

			// hlineto/vlineto and vhcurveto/hvcurveto alternate horizontal and vertical
			// starting from a different place.

		case 0x07: // vlineto
			if (sp < 1) return STBTT__CSERR("vlineto stack");
			goto vlineto;
		case 0x06: // hlineto
			if (sp < 1) return STBTT__CSERR("hlineto stack");
			for (;;) {
				if (i >= sp) break;
				stbtt__csctx_rline_to(c, s[i], 0);
				i++;
			vlineto:
				if (i >= sp) break;
				stbtt__csctx_rline_to(c, 0, s[i]);
				i++;
			}
			break;

		case 0x1F: // hvcurveto
			if (sp < 4) return STBTT__CSERR("hvcurveto stack");
			goto hvcurveto;
		case 0x1E: // vhcurveto
			if (sp < 4) return STBTT__CSERR("vhcurveto stack");
			for (;;) {
				if (i + 3 >= sp) break;
				stbtt__csctx_rccurve_to(c, 0, s[i], s[i + 1], s[i + 2], s[i + 3], (sp - i == 5) ? s[i + 4] : 0.0f);
				i += 4;
			hvcurveto:
				if (i + 3 >= sp) break;
				stbtt__csctx_rccurve_to(c, s[i], 0, s[i + 1], s[i + 2], (sp - i == 5) ? s[i + 4] : 0.0f, s[i + 3]);
				i += 4;
			}
			break;

		case 0x08: // rrcurveto
			if (sp < 6) return STBTT__CSERR("rcurveline stack");
			for (; i + 5 < sp; i += 6)
				stbtt__csctx_rccurve_to(c, s[i], s[i + 1], s[i + 2], s[i + 3], s[i + 4], s[i + 5]);
			break;

		case 0x18: // rcurveline
			if (sp < 8) return STBTT__CSERR("rcurveline stack");
			for (; i + 5 < sp - 2; i += 6)
				stbtt__csctx_rccurve_to(c, s[i], s[i + 1], s[i + 2], s[i + 3], s[i + 4], s[i + 5]);
			if (i + 1 >= sp) return STBTT__CSERR("rcurveline stack");
			stbtt__csctx_rline_to(c, s[i], s[i + 1]);
			break;

		case 0x19: // rlinecurve
			if (sp < 8) return STBTT__CSERR("rlinecurve stack");
			for (; i + 1 < sp - 6; i += 2)
				stbtt__csctx_rline_to(c, s[i], s[i + 1]);
			if (i + 5 >= sp) return STBTT__CSERR("rlinecurve stack");
			stbtt__csctx_rccurve_to(c, s[i], s[i + 1], s[i + 2], s[i + 3], s[i + 4], s[i + 5]);
			break;

		case 0x1A: // vvcurveto
		case 0x1B: // hhcurveto
			if (sp < 4) return STBTT__CSERR("(vv|hh)curveto stack");
			f = 0.0;
			if (sp & 1) { f = s[i]; i++; }
			for (; i + 3 < sp; i += 4) {
				if (b0 == 0x1B)
					stbtt__csctx_rccurve_to(c, s[i], f, s[i + 1], s[i + 2], s[i + 3], 0.0);
				else
					stbtt__csctx_rccurve_to(c, f, s[i], s[i + 1], s[i + 2], 0.0, s[i + 3]);
				f = 0.0;
			}
			break;

		case 0x0A: // callsubr
			if (!has_subrs) {
				if (info->fdselect.size)
					subrs = stbtt__cid_get_glyph_subrs(info, glyph_index);
				has_subrs = 1;
			}
			// fallthrough
		case 0x1D: // callgsubr
			if (sp < 1) return STBTT__CSERR("call(g|)subr stack");
			v = (int)s[--sp];
			if (subr_stack_height >= 10) return STBTT__CSERR("recursion limit");
			subr_stack[subr_stack_height++] = b;
			b = stbtt__get_subr(b0 == 0x0A ? subrs : info->gsubrs, v);
			if (b.size == 0) return STBTT__CSERR("subr not found");
			b.cursor = 0;
			clear_stack = 0;
			break;

		case 0x0B: // return
			if (subr_stack_height <= 0) return STBTT__CSERR("return outside subr");
			b = subr_stack[--subr_stack_height];
			clear_stack = 0;
			break;

		case 0x0E: // endchar
			stbtt__csctx_close_shape(c);
			return 1;

		case 0x0C: { // two-byte escape
			float dx1, dx2, dx3, dx4, dx5, dx6, dy1, dy2, dy3, dy4, dy5, dy6;
			float dx, dy;
			int b1 = stbtt__buf_get8(&b);
			switch (b1) {
				// @TODO These "flex" implementations ignore the flex-depth and resolution,
				// and always draw beziers.
			case 0x22: // hflex
				if (sp < 7) return STBTT__CSERR("hflex stack");
				dx1 = s[0];
				dx2 = s[1];
				dy2 = s[2];
				dx3 = s[3];
				dx4 = s[4];
				dx5 = s[5];
				dx6 = s[6];
				stbtt__csctx_rccurve_to(c, dx1, 0, dx2, dy2, dx3, 0);
				stbtt__csctx_rccurve_to(c, dx4, 0, dx5, -dy2, dx6, 0);
				break;

			case 0x23: // flex
				if (sp < 13) return STBTT__CSERR("flex stack");
				dx1 = s[0];
				dy1 = s[1];
				dx2 = s[2];
				dy2 = s[3];
				dx3 = s[4];
				dy3 = s[5];
				dx4 = s[6];
				dy4 = s[7];
				dx5 = s[8];
				dy5 = s[9];
				dx6 = s[10];
				dy6 = s[11];
				//fd is s[12]
				stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3);
				stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6);
				break;

			case 0x24: // hflex1
				if (sp < 9) return STBTT__CSERR("hflex1 stack");
				dx1 = s[0];
				dy1 = s[1];
				dx2 = s[2];
				dy2 = s[3];
				dx3 = s[4];
				dx4 = s[5];
				dx5 = s[6];
				dy5 = s[7];
				dx6 = s[8];
				stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, 0);
				stbtt__csctx_rccurve_to(c, dx4, 0, dx5, dy5, dx6, -(dy1 + dy2 + dy5));
				break;

			case 0x25: // flex1
				if (sp < 11) return STBTT__CSERR("flex1 stack");
				dx1 = s[0];
				dy1 = s[1];
				dx2 = s[2];
				dy2 = s[3];
				dx3 = s[4];
				dy3 = s[5];
				dx4 = s[6];
				dy4 = s[7];
				dx5 = s[8];
				dy5 = s[9];
				dx6 = dy6 = s[10];
				dx = dx1 + dx2 + dx3 + dx4 + dx5;
				dy = dy1 + dy2 + dy3 + dy4 + dy5;
				if (STBTT_fabs(dx) > STBTT_fabs(dy))
					dy6 = -dy;
				else
					dx6 = -dx;
				stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3);
				stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6);
				break;

			default:
				return STBTT__CSERR("unimplemented");
			}
		} break;

		default:
			if (b0 != 255 && b0 != 28 && (b0 < 32 || b0 > 254))
				return STBTT__CSERR("reserved operator");

			// push immediate
			if (b0 == 255) {
				f = (float)stbtt__buf_get32(&b) / 0x10000;
			}
			else {
				stbtt__buf_skip(&b, -1);
				f = (float)(stbtt_int16)stbtt__cff_int(&b);
			}
			if (sp >= 48) return STBTT__CSERR("push stack overflow");
			s[sp++] = f;
			clear_stack = 0;
			break;
		}
		if (clear_stack) sp = 0;
	}
	return STBTT__CSERR("no endchar");

#undef STBTT__CSERR
}

static int stbtt__GetGlyphShapeT2(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
{
	// runs the charstring twice, once to count and once to output (to avoid realloc)
	stbtt__csctx count_ctx = STBTT__CSCTX_INIT(1);
	stbtt__csctx output_ctx = STBTT__CSCTX_INIT(0);
	if (stbtt__run_charstring(info, glyph_index, &count_ctx)) {
		*pvertices = (stbtt_vertex*)STBTT_malloc(count_ctx.num_vertices * sizeof(stbtt_vertex), info->userdata);
		output_ctx.pvertices = *pvertices;
		if (stbtt__run_charstring(info, glyph_index, &output_ctx)) {
			STBTT_assert(output_ctx.num_vertices == count_ctx.num_vertices);
			return output_ctx.num_vertices;
		}
	}
	*pvertices = NULL;
	return 0;
}

static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
{
	stbtt__csctx c = STBTT__CSCTX_INIT(1);
	int r = stbtt__run_charstring(info, glyph_index, &c);
	if (x0) {
		*x0 = r ? c.min_x : 0;
		*y0 = r ? c.min_y : 0;
		*x1 = r ? c.max_x : 0;
		*y1 = r ? c.max_y : 0;
	}
	return r ? c.num_vertices : 0;
}

STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
{
	if (!info->cff.size)
		return stbtt__GetGlyphShapeTT(info, glyph_index, pvertices);
	else
		return stbtt__GetGlyphShapeT2(info, glyph_index, pvertices);
}

STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing)
{
	stbtt_uint16 numOfLongHorMetrics = ttUSHORT(info->data + info->hhea + 34);
	if (glyph_index < numOfLongHorMetrics) {
		if (advanceWidth)     *advanceWidth = ttSHORT(info->data + info->hmtx + 4 * glyph_index);
		if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4 * glyph_index + 2);
	}
	else {
		if (advanceWidth)     *advanceWidth = ttSHORT(info->data + info->hmtx + 4 * (numOfLongHorMetrics - 1));
		if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4 * numOfLongHorMetrics + 2 * (glyph_index - numOfLongHorMetrics));
	}
}

STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
{
	stbtt_uint8 *data = info->data + info->kern;
	stbtt_uint32 needle, straw;
	int l, r, m;

	// we only look at the first table. it must be 'horizontal' and format 0.
	if (!info->kern)
		return 0;
	if (ttUSHORT(data + 2) < 1) // number of tables, need at least 1
		return 0;
	if (ttUSHORT(data + 8) != 1) // horizontal flag must be set in format
		return 0;

	l = 0;
	r = ttUSHORT(data + 10) - 1;
	needle = glyph1 << 16 | glyph2;
	while (l <= r) {
		m = (l + r) >> 1;
		straw = ttULONG(data + 18 + (m * 6)); // note: unaligned read
		if (needle < straw)
			r = m - 1;
		else if (needle > straw)
			l = m + 1;
		else
			return ttSHORT(data + 22 + (m * 6));
	}
	return 0;
}

STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2)
{
	if (!info->kern) // if no kerning table, don't waste time looking up both codepoint->glyphs
		return 0;
	return stbtt_GetGlyphKernAdvance(info, stbtt_FindGlyphIndex(info, ch1), stbtt_FindGlyphIndex(info, ch2));
}

STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing)
{
	stbtt_GetGlyphHMetrics(info, stbtt_FindGlyphIndex(info, codepoint), advanceWidth, leftSideBearing);
}

STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap)
{
	if (ascent) *ascent = ttSHORT(info->data + info->hhea + 4);
	if (descent) *descent = ttSHORT(info->data + info->hhea + 6);
	if (lineGap) *lineGap = ttSHORT(info->data + info->hhea + 8);
}

STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1)
{
	*x0 = ttSHORT(info->data + info->head + 36);
	*y0 = ttSHORT(info->data + info->head + 38);
	*x1 = ttSHORT(info->data + info->head + 40);
	*y1 = ttSHORT(info->data + info->head + 42);
}

STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float height)
{
	int fheight = ttSHORT(info->data + info->hhea + 4) - ttSHORT(info->data + info->hhea + 6);
	return (float)height / fheight;
}

STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels)
{
	int unitsPerEm = ttUSHORT(info->data + info->head + 18);
	return pixels / unitsPerEm;
}

STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *v)
{
	STBTT_free(v, info->userdata);
}

//////////////////////////////////////////////////////////////////////////////
//
// antialiasing software rasterizer
//

STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
{
	int x0 = 0, y0 = 0, x1, y1; // =0 suppresses compiler warning
	if (!stbtt_GetGlyphBox(font, glyph, &x0, &y0, &x1, &y1)) {
		// e.g. space character
		if (ix0) *ix0 = 0;
		if (iy0) *iy0 = 0;
		if (ix1) *ix1 = 0;
		if (iy1) *iy1 = 0;
	}
	else {
		// move to integral bboxes (treating pixels as little squares, what pixels get touched)?
		if (ix0) *ix0 = STBTT_ifloor(x0 * scale_x + shift_x);
		if (iy0) *iy0 = STBTT_ifloor(-y1 * scale_y + shift_y);
		if (ix1) *ix1 = STBTT_iceil(x1 * scale_x + shift_x);
		if (iy1) *iy1 = STBTT_iceil(-y0 * scale_y + shift_y);
	}
}

STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
{
	stbtt_GetGlyphBitmapBoxSubpixel(font, glyph, scale_x, scale_y, 0.0f, 0.0f, ix0, iy0, ix1, iy1);
}

STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
{
	stbtt_GetGlyphBitmapBoxSubpixel(font, stbtt_FindGlyphIndex(font, codepoint), scale_x, scale_y, shift_x, shift_y, ix0, iy0, ix1, iy1);
}

STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
{
	stbtt_GetCodepointBitmapBoxSubpixel(font, codepoint, scale_x, scale_y, 0.0f, 0.0f, ix0, iy0, ix1, iy1);
}

//////////////////////////////////////////////////////////////////////////////
//
//  Rasterizer

typedef struct stbtt__hheap_chunk
{
	struct stbtt__hheap_chunk *next;
} stbtt__hheap_chunk;

typedef struct stbtt__hheap
{
	struct stbtt__hheap_chunk *head;
	void   *first_free;
	int    num_remaining_in_head_chunk;
} stbtt__hheap;

static void *stbtt__hheap_alloc(stbtt__hheap *hh, size_t size, void *userdata)
{
	if (hh->first_free) {
		void *p = hh->first_free;
		hh->first_free = *(void **)p;
		return p;
	}
	else {
		if (hh->num_remaining_in_head_chunk == 0) {
			int count = (size < 32 ? 2000 : size < 128 ? 800 : 100);
			stbtt__hheap_chunk *c = (stbtt__hheap_chunk *)STBTT_malloc(sizeof(stbtt__hheap_chunk) + size * count, userdata);
			if (c == NULL)
				return NULL;
			c->next = hh->head;
			hh->head = c;
			hh->num_remaining_in_head_chunk = count;
		}
		--hh->num_remaining_in_head_chunk;
		return (char *)(hh->head) + size * hh->num_remaining_in_head_chunk;
	}
}

static void stbtt__hheap_free(stbtt__hheap *hh, void *p)
{
	*(void **)p = hh->first_free;
	hh->first_free = p;
}

static void stbtt__hheap_cleanup(stbtt__hheap *hh, void *userdata)
{
	stbtt__hheap_chunk *c = hh->head;
	while (c) {
		stbtt__hheap_chunk *n = c->next;
		STBTT_free(c, userdata);
		c = n;
	}
}

typedef struct stbtt__edge {
	float x0, y0, x1, y1;
	int invert;
} stbtt__edge;


typedef struct stbtt__active_edge
{
	struct stbtt__active_edge *next;
#if STBTT_RASTERIZER_VERSION==1
	int x, dx;
	float ey;
	int direction;
#elif STBTT_RASTERIZER_VERSION==2
	float fx, fdx, fdy;
	float direction;
	float sy;
	float ey;
#else
////#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif
} stbtt__active_edge;

#if STBTT_RASTERIZER_VERSION == 1
#define STBTT_FIXSHIFT   10
#define STBTT_FIX        (1 << STBTT_FIXSHIFT)
#define STBTT_FIXMASK    (STBTT_FIX-1)

static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
{
	stbtt__active_edge *z = (stbtt__active_edge *)stbtt__hheap_alloc(hh, sizeof(*z), userdata);
	float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
	STBTT_assert(z != NULL);
	if (!z) return z;

	// round dx down to avoid overshooting
	if (dxdy < 0)
		z->dx = -STBTT_ifloor(STBTT_FIX * -dxdy);
	else
		z->dx = STBTT_ifloor(STBTT_FIX * dxdy);

	z->x = STBTT_ifloor(STBTT_FIX * e->x0 + z->dx * (start_point - e->y0)); // use z->dx so when we offset later it's by the same amount
	z->x -= off_x * STBTT_FIX;

	z->ey = e->y1;
	z->next = 0;
	z->direction = e->invert ? 1 : -1;
	return z;
}
#elif STBTT_RASTERIZER_VERSION == 2
static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
{
	stbtt__active_edge *z = (stbtt__active_edge *)stbtt__hheap_alloc(hh, sizeof(*z), userdata);
	float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
	STBTT_assert(z != NULL);
	//STBTT_assert(e->y0 <= start_point);
	if (!z) return z;
	z->fdx = dxdy;
	z->fdy = dxdy != 0.0f ? (1.0f / dxdy) : 0.0f;
	z->fx = e->x0 + dxdy * (start_point - e->y0);
	z->fx -= off_x;
	z->direction = e->invert ? 1.0f : -1.0f;
	z->sy = e->y0;
	z->ey = e->y1;
	z->next = 0;
	return z;
}
#else
//#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif

#if STBTT_RASTERIZER_VERSION == 1
// note: this routine clips fills that extend off the edges... ideally this
// wouldn't happen, but it could happen if the truetype glyph bounding boxes
// are wrong, or if the user supplies a too-small bitmap
static void stbtt__fill_active_edges(unsigned char *scanline, int len, stbtt__active_edge *e, int max_weight)
{
	// non-zero winding fill
	int x0 = 0, w = 0;

	while (e) {
		if (w == 0) {
			// if we're currently at zero, we need to record the edge start point
			x0 = e->x; w += e->direction;
		}
		else {
			int x1 = e->x; w += e->direction;
			// if we went to zero, we need to draw
			if (w == 0) {
				int i = x0 >> STBTT_FIXSHIFT;
				int j = x1 >> STBTT_FIXSHIFT;

				if (i < len && j >= 0) {
					if (i == j) {
						// x0,x1 are the same pixel, so compute combined coverage
						scanline[i] = scanline[i] + (stbtt_uint8)((x1 - x0) * max_weight >> STBTT_FIXSHIFT);
					}
					else {
						if (i >= 0) // add antialiasing for x0
							scanline[i] = scanline[i] + (stbtt_uint8)(((STBTT_FIX - (x0 & STBTT_FIXMASK)) * max_weight) >> STBTT_FIXSHIFT);
						else
							i = -1; // clip

						if (j < len) // add antialiasing for x1
							scanline[j] = scanline[j] + (stbtt_uint8)(((x1 & STBTT_FIXMASK) * max_weight) >> STBTT_FIXSHIFT);
						else
							j = len; // clip

						for (++i; i < j; ++i) // fill pixels between x0 and x1
							scanline[i] = scanline[i] + (stbtt_uint8)max_weight;
					}
				}
			}
		}

		e = e->next;
	}
}

static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
{
	stbtt__hheap hh = { 0, 0, 0 };
	stbtt__active_edge *active = NULL;
	int y, j = 0;
	int max_weight = (255 / vsubsample);  // weight per vertical scanline
	int s; // vertical subsample index
	unsigned char scanline_data[512], *scanline;

	if (result->w > 512)
		scanline = (unsigned char *)STBTT_malloc(result->w, userdata);
	else
		scanline = scanline_data;

	y = off_y * vsubsample;
	e[n].y0 = (off_y + result->h) * (float)vsubsample + 1;

	while (j < result->h) {
		STBTT_memset(scanline, 0, result->w);
		for (s = 0; s < vsubsample; ++s) {
			// find center of pixel for this scanline
			float scan_y = y + 0.5f;
			stbtt__active_edge **step = &active;

			// update all active edges;
			// remove all active edges that terminate before the center of this scanline
			while (*step) {
				stbtt__active_edge * z = *step;
				if (z->ey <= scan_y) {
					*step = z->next; // delete from list
					STBTT_assert(z->direction);
					z->direction = 0;
					stbtt__hheap_free(&hh, z);
				}
				else {
					z->x += z->dx; // advance to position for current scanline
					step = &((*step)->next); // advance through list
				}
			}

			// resort the list if needed
			for (;;) {
				int changed = 0;
				step = &active;
				while (*step && (*step)->next) {
					if ((*step)->x > (*step)->next->x) {
						stbtt__active_edge *t = *step;
						stbtt__active_edge *q = t->next;

						t->next = q->next;
						q->next = t;
						*step = q;
						changed = 1;
					}
					step = &(*step)->next;
				}
				if (!changed) break;
			}

			// insert all edges that start before the center of this scanline -- omit ones that also end on this scanline
			while (e->y0 <= scan_y) {
				if (e->y1 > scan_y) {
					stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y, userdata);
					if (z != NULL) {
						// find insertion point
						if (active == NULL)
							active = z;
						else if (z->x < active->x) {
							// insert at front
							z->next = active;
							active = z;
						}
						else {
							// find thing to insert AFTER
							stbtt__active_edge *p = active;
							while (p->next && p->next->x < z->x)
								p = p->next;
							// at this point, p->next->x is NOT < z->x
							z->next = p->next;
							p->next = z;
						}
					}
				}
				++e;
			}

			// now process all active edges in XOR fashion
			if (active)
				stbtt__fill_active_edges(scanline, result->w, active, max_weight);

			++y;
		}
		STBTT_memcpy(result->pixels + j * result->stride, scanline, result->w);
		++j;
	}

	stbtt__hheap_cleanup(&hh, userdata);

	if (scanline != scanline_data)
		STBTT_free(scanline, userdata);
}

#elif STBTT_RASTERIZER_VERSION == 2

// the edge passed in here does not cross the vertical line at x or the vertical line at x+1
// (i.e. it has already been clipped to those)
static void stbtt__handle_clipped_edge(float *scanline, int x, stbtt__active_edge *e, float x0, float y0, float x1, float y1)
{
	if (y0 == y1) return;
	STBTT_assert(y0 < y1);
	STBTT_assert(e->sy <= e->ey);
	if (y0 > e->ey) return;
	if (y1 < e->sy) return;
	if (y0 < e->sy) {
		x0 += (x1 - x0) * (e->sy - y0) / (y1 - y0);
		y0 = e->sy;
	}
	if (y1 > e->ey) {
		x1 += (x1 - x0) * (e->ey - y1) / (y1 - y0);
		y1 = e->ey;
	}

	if (x0 == x)
		STBTT_assert(x1 <= x + 1);
	else if (x0 == x + 1)
		STBTT_assert(x1 >= x);
	else if (x0 <= x)
		STBTT_assert(x1 <= x);
	else if (x0 >= x + 1)
		STBTT_assert(x1 >= x + 1);
	else
		STBTT_assert(x1 >= x && x1 <= x + 1);

	if (x0 <= x && x1 <= x)
		scanline[x] += e->direction * (y1 - y0);
	else if (x0 >= x + 1 && x1 >= x + 1)
		;
	else {
		STBTT_assert(x0 >= x && x0 <= x + 1 && x1 >= x && x1 <= x + 1);
		scanline[x] += e->direction * (y1 - y0) * (1 - ((x0 - x) + (x1 - x)) / 2); // coverage = 1 - average x position
	}
}

static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top)
{
	float y_bottom = y_top + 1;

	while (e) {
		// brute force every pixel

		// compute intersection points with top & bottom
		STBTT_assert(e->ey >= y_top);

		if (e->fdx == 0) {
			float x0 = e->fx;
			if (x0 < len) {
				if (x0 >= 0) {
					stbtt__handle_clipped_edge(scanline, (int)x0, e, x0, y_top, x0, y_bottom);
					stbtt__handle_clipped_edge(scanline_fill - 1, (int)x0 + 1, e, x0, y_top, x0, y_bottom);
				}
				else {
					stbtt__handle_clipped_edge(scanline_fill - 1, 0, e, x0, y_top, x0, y_bottom);
				}
			}
		}
		else {
			float x0 = e->fx;
			float dx = e->fdx;
			float xb = x0 + dx;
			float x_top, x_bottom;
			float sy0, sy1;
			float dy = e->fdy;
			STBTT_assert(e->sy <= y_bottom && e->ey >= y_top);

			// compute endpoints of line segment clipped to this scanline (if the
			// line segment starts on this scanline. x0 is the intersection of the
			// line with y_top, but that may be off the line segment.
			if (e->sy > y_top) {
				x_top = x0 + dx * (e->sy - y_top);
				sy0 = e->sy;
			}
			else {
				x_top = x0;
				sy0 = y_top;
			}
			if (e->ey < y_bottom) {
				x_bottom = x0 + dx * (e->ey - y_top);
				sy1 = e->ey;
			}
			else {
				x_bottom = xb;
				sy1 = y_bottom;
			}

			if (x_top >= 0 && x_bottom >= 0 && x_top < len && x_bottom < len) {
				// from here on, we don't have to range check x values

				if ((int)x_top == (int)x_bottom) {
					float height;
					// simple case, only spans one pixel
					int x = (int)x_top;
					height = sy1 - sy0;
					STBTT_assert(x >= 0 && x < len);
					scanline[x] += e->direction * (1 - ((x_top - x) + (x_bottom - x)) / 2)  * height;
					scanline_fill[x] += e->direction * height; // everything right of this pixel is filled
				}
				else {
					int x, x1, x2;
					float y_crossing, step, sign, area;
					// covers 2+ pixels
					if (x_top > x_bottom) {
						// flip scanline vertically; signed area is the same
						float t;
						sy0 = y_bottom - (sy0 - y_top);
						sy1 = y_bottom - (sy1 - y_top);
						t = sy0, sy0 = sy1, sy1 = t;
						t = x_bottom, x_bottom = x_top, x_top = t;
						dx = -dx;
						dy = -dy;
						t = x0, x0 = xb, xb = t;
					}

					x1 = (int)x_top;
					x2 = (int)x_bottom;
					// compute intersection with y axis at x1+1
					y_crossing = (x1 + 1 - x0) * dy + y_top;

					sign = e->direction;
					// area of the rectangle covered from y0..y_crossing
					area = sign * (y_crossing - sy0);
					// area of the triangle (x_top,y0), (x+1,y0), (x+1,y_crossing)
					scanline[x1] += area * (1 - ((x_top - x1) + (x1 + 1 - x1)) / 2);

					step = sign * dy;
					for (x = x1 + 1; x < x2; ++x) {
						scanline[x] += area + step / 2;
						area += step;
					}
					y_crossing += dy * (x2 - (x1 + 1));

					STBTT_assert(STBTT_fabs(area) <= 1.01f);

					scanline[x2] += area + sign * (1 - ((x2 - x2) + (x_bottom - x2)) / 2) * (sy1 - y_crossing);

					scanline_fill[x2] += sign * (sy1 - sy0);
				}
			}
			else {
				// if edge goes outside of box we're drawing, we require
				// clipping logic. since this does not match the intended use
				// of this library, we use a different, very slow brute
				// force implementation
				int x;
				for (x = 0; x < len; ++x) {
					// cases:
					//
					// there can be up to two intersections with the pixel. any intersection
					// with left or right edges can be handled by splitting into two (or three)
					// regions. intersections with top & bottom do not necessitate case-wise logic.
					//
					// the old way of doing this found the intersections with the left & right edges,
					// then used some simple logic to produce up to three segments in sorted order
					// from top-to-bottom. however, this had a problem: if an x edge was epsilon
					// across the x border, then the corresponding y position might not be distinct
					// from the other y segment, and it might ignored as an empty segment. to avoid
					// that, we need to explicitly produce segments based on x positions.

					// rename variables to clear pairs
					float y0 = y_top;
					float x1 = (float)(x);
					float x2 = (float)(x + 1);
					float x3 = xb;
					float y3 = y_bottom;
					float y1, y2;

					// x = e->x + e->dx * (y-y_top)
					// (y-y_top) = (x - e->x) / e->dx
					// y = (x - e->x) / e->dx + y_top
					y1 = (x - x0) / dx + y_top;
					y2 = (x + 1 - x0) / dx + y_top;

					if (x0 < x1 && x3 > x2) {         // three segments descending down-right
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x1, y1);
						stbtt__handle_clipped_edge(scanline, x, e, x1, y1, x2, y2);
						stbtt__handle_clipped_edge(scanline, x, e, x2, y2, x3, y3);
					}
					else if (x3 < x1 && x0 > x2) {  // three segments descending down-left
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x2, y2);
						stbtt__handle_clipped_edge(scanline, x, e, x2, y2, x1, y1);
						stbtt__handle_clipped_edge(scanline, x, e, x1, y1, x3, y3);
					}
					else if (x0 < x1 && x3 > x1) {  // two segments across x, down-right
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x1, y1);
						stbtt__handle_clipped_edge(scanline, x, e, x1, y1, x3, y3);
					}
					else if (x3 < x1 && x0 > x1) {  // two segments across x, down-left
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x1, y1);
						stbtt__handle_clipped_edge(scanline, x, e, x1, y1, x3, y3);
					}
					else if (x0 < x2 && x3 > x2) {  // two segments across x+1, down-right
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x2, y2);
						stbtt__handle_clipped_edge(scanline, x, e, x2, y2, x3, y3);
					}
					else if (x3 < x2 && x0 > x2) {  // two segments across x+1, down-left
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x2, y2);
						stbtt__handle_clipped_edge(scanline, x, e, x2, y2, x3, y3);
					}
					else {  // one segment
						stbtt__handle_clipped_edge(scanline, x, e, x0, y0, x3, y3);
					}
				}
			}
		}
		e = e->next;
	}
}

// directly AA rasterize edges w/o supersampling
static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
{
	stbtt__hheap hh = { 0, 0, 0 };
	stbtt__active_edge *active = NULL;
	int y, j = 0, i;
	float scanline_data[129], *scanline, *scanline2;

	STBTT__NOTUSED(vsubsample);

	if (result->w > 64)
		scanline = (float *)STBTT_malloc((result->w * 2 + 1) * sizeof(float), userdata);
	else
		scanline = scanline_data;

	scanline2 = scanline + result->w;

	y = off_y;
	e[n].y0 = (float)(off_y + result->h) + 1;

	while (j < result->h) {
		// find center of pixel for this scanline
		float scan_y_top = y + 0.0f;
		float scan_y_bottom = y + 1.0f;
		stbtt__active_edge **step = &active;

		STBTT_memset(scanline, 0, result->w * sizeof(scanline[0]));
		STBTT_memset(scanline2, 0, (result->w + 1) * sizeof(scanline[0]));

		// update all active edges;
		// remove all active edges that terminate before the top of this scanline
		while (*step) {
			stbtt__active_edge * z = *step;
			if (z->ey <= scan_y_top) {
				*step = z->next; // delete from list
				STBTT_assert(z->direction);
				z->direction = 0;
				stbtt__hheap_free(&hh, z);
			}
			else {
				step = &((*step)->next); // advance through list
			}
		}

		// insert all edges that start before the bottom of this scanline
		while (e->y0 <= scan_y_bottom) {
			if (e->y0 != e->y1) {
				stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y_top, userdata);
				if (z != NULL) {
					STBTT_assert(z->ey >= scan_y_top);
					// insert at front
					z->next = active;
					active = z;
				}
			}
			++e;
		}

		// now process all active edges
		if (active)
			stbtt__fill_active_edges_new(scanline, scanline2 + 1, result->w, active, scan_y_top);

		{
			float sum = 0;
			for (i = 0; i < result->w; ++i) {
				float k;
				int m;
				sum += scanline2[i];
				k = scanline[i] + sum;
				k = (float)STBTT_fabs(k) * 255 + 0.5f;
				m = (int)k;
				if (m > 255) m = 255;
				result->pixels[j*result->stride + i] = (unsigned char)m;
			}
		}
		// advance all the edges
		step = &active;
		while (*step) {
			stbtt__active_edge *z = *step;
			z->fx += z->fdx; // advance to position for current scanline
			step = &((*step)->next); // advance through list
		}

		++y;
		++j;
	}

	stbtt__hheap_cleanup(&hh, userdata);

	if (scanline != scanline_data)
		STBTT_free(scanline, userdata);
}
#else
//#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif

#define STBTT__COMPARE(a,b)  ((a)->y0 < (b)->y0)

static void stbtt__sort_edges_ins_sort(stbtt__edge *p, int n)
{
	int i, j;
	for (i = 1; i < n; ++i) {
		stbtt__edge t = p[i], *a = &t;
		j = i;
		while (j > 0) {
			stbtt__edge *b = &p[j - 1];
			int c = STBTT__COMPARE(a, b);
			if (!c) break;
			p[j] = p[j - 1];
			--j;
		}
		if (i != j)
			p[j] = t;
	}
}

static void stbtt__sort_edges_quicksort(stbtt__edge *p, int n)
{
	/* threshhold for transitioning to insertion sort */
	while (n > 12) {
		stbtt__edge t;
		int c01, c12, c, m, i, j;

		/* compute median of three */
		m = n >> 1;
		c01 = STBTT__COMPARE(&p[0], &p[m]);
		c12 = STBTT__COMPARE(&p[m], &p[n - 1]);
		/* if 0 >= mid >= end, or 0 < mid < end, then use mid */
		if (c01 != c12) {
			/* otherwise, we'll need to swap something else to middle */
			int z;
			c = STBTT__COMPARE(&p[0], &p[n - 1]);
			/* 0>mid && mid<n:  0>n => n; 0<n => 0 */
			/* 0<mid && mid>n:  0>n => 0; 0<n => n */
			z = (c == c12) ? 0 : n - 1;
			t = p[z];
			p[z] = p[m];
			p[m] = t;
		}
		/* now p[m] is the median-of-three */
		/* swap it to the beginning so it won't move around */
		t = p[0];
		p[0] = p[m];
		p[m] = t;

		/* partition loop */
		i = 1;
		j = n - 1;
		for (;;) {
			/* handling of equality is crucial here */
			/* for sentinels & efficiency with duplicates */
			for (;; ++i) {
				if (!STBTT__COMPARE(&p[i], &p[0])) break;
			}
			for (;; --j) {
				if (!STBTT__COMPARE(&p[0], &p[j])) break;
			}
			/* make sure we haven't crossed */
			if (i >= j) break;
			t = p[i];
			p[i] = p[j];
			p[j] = t;

			++i;
			--j;
		}
		/* recurse on smaller side, iterate on larger */
		if (j < (n - i)) {
			stbtt__sort_edges_quicksort(p, j);
			p = p + i;
			n = n - i;
		}
		else {
			stbtt__sort_edges_quicksort(p + i, n - i);
			n = j;
		}
	}
}

static void stbtt__sort_edges(stbtt__edge *p, int n)
{
	stbtt__sort_edges_quicksort(p, n);
	stbtt__sort_edges_ins_sort(p, n);
}

typedef struct
{
	float x, y;
} stbtt__point;

static void stbtt__rasterize(stbtt__bitmap *result, stbtt__point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata)
{
	float y_scale_inv = invert ? -scale_y : scale_y;
	stbtt__edge *e;
	int n, i, j, k, m;
#if STBTT_RASTERIZER_VERSION == 1
	int vsubsample = result->h < 8 ? 15 : 5;
#elif STBTT_RASTERIZER_VERSION == 2
	int vsubsample = 1;
#else
//#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
#endif
	// vsubsample should divide 255 evenly; otherwise we won't reach full opacity

	// now we have to blow out the windings into explicit edge lists
	n = 0;
	for (i = 0; i < windings; ++i)
		n += wcount[i];

	e = (stbtt__edge *)STBTT_malloc(sizeof(*e) * (n + 1), userdata); // add an extra one as a sentinel
	if (e == 0) return;
	n = 0;

	m = 0;
	for (i = 0; i < windings; ++i) {
		stbtt__point *p = pts + m;
		m += wcount[i];
		j = wcount[i] - 1;
		for (k = 0; k < wcount[i]; j = k++) {
			int a = k, b = j;
			// skip the edge if horizontal
			if (p[j].y == p[k].y)
				continue;
			// add edge from j to k to the list
			e[n].invert = 0;
			if (invert ? p[j].y > p[k].y : p[j].y < p[k].y) {
				e[n].invert = 1;
				a = j, b = k;
			}
			e[n].x0 = p[a].x * scale_x + shift_x;
			e[n].y0 = (p[a].y * y_scale_inv + shift_y) * vsubsample;
			e[n].x1 = p[b].x * scale_x + shift_x;
			e[n].y1 = (p[b].y * y_scale_inv + shift_y) * vsubsample;
			++n;
		}
	}

	// now sort the edges by their highest point (should snap to integer, and then by x)
	//STBTT_sort(e, n, sizeof(e[0]), stbtt__edge_compare);
	stbtt__sort_edges(e, n);

	// now, traverse the scanlines and find the intersections on each scanline, use xor winding rule
	stbtt__rasterize_sorted_edges(result, e, n, vsubsample, off_x, off_y, userdata);

	STBTT_free(e, userdata);
}

static void stbtt__add_point(stbtt__point *points, int n, float x, float y)
{
	if (!points) return; // during first pass, it's unallocated
	points[n].x = x;
	points[n].y = y;
}

// tesselate until threshhold p is happy... @TODO warped to compensate for non-linear stretching
static int stbtt__tesselate_curve(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float objspace_flatness_squared, int n)
{
	// midpoint
	float mx = (x0 + 2 * x1 + x2) / 4;
	float my = (y0 + 2 * y1 + y2) / 4;
	// versus directly drawn line
	float dx = (x0 + x2) / 2 - mx;
	float dy = (y0 + y2) / 2 - my;
	if (n > 16) // 65536 segments on one curve better be enough!
		return 1;
	if (dx*dx + dy*dy > objspace_flatness_squared) { // half-pixel error allowed... need to be smaller if AA
		stbtt__tesselate_curve(points, num_points, x0, y0, (x0 + x1) / 2.0f, (y0 + y1) / 2.0f, mx, my, objspace_flatness_squared, n + 1);
		stbtt__tesselate_curve(points, num_points, mx, my, (x1 + x2) / 2.0f, (y1 + y2) / 2.0f, x2, y2, objspace_flatness_squared, n + 1);
	}
	else {
		stbtt__add_point(points, *num_points, x2, y2);
		*num_points = *num_points + 1;
	}
	return 1;
}

static void stbtt__tesselate_cubic(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float x3, float y3, float objspace_flatness_squared, int n)
{
	// @TODO this "flatness" calculation is just made-up nonsense that seems to work well enough
	float dx0 = x1 - x0;
	float dy0 = y1 - y0;
	float dx1 = x2 - x1;
	float dy1 = y2 - y1;
	float dx2 = x3 - x2;
	float dy2 = y3 - y2;
	float dx = x3 - x0;
	float dy = y3 - y0;
	float longlen = (float)(STBTT_sqrt(dx0*dx0 + dy0*dy0) + STBTT_sqrt(dx1*dx1 + dy1*dy1) + STBTT_sqrt(dx2*dx2 + dy2*dy2));
	float shortlen = (float)STBTT_sqrt(dx*dx + dy*dy);
	float flatness_squared = longlen*longlen - shortlen*shortlen;

	if (n > 16) // 65536 segments on one curve better be enough!
		return;

	if (flatness_squared > objspace_flatness_squared) {
		float x01 = (x0 + x1) / 2;
		float y01 = (y0 + y1) / 2;
		float x12 = (x1 + x2) / 2;
		float y12 = (y1 + y2) / 2;
		float x23 = (x2 + x3) / 2;
		float y23 = (y2 + y3) / 2;

		float xa = (x01 + x12) / 2;
		float ya = (y01 + y12) / 2;
		float xb = (x12 + x23) / 2;
		float yb = (y12 + y23) / 2;

		float mx = (xa + xb) / 2;
		float my = (ya + yb) / 2;

		stbtt__tesselate_cubic(points, num_points, x0, y0, x01, y01, xa, ya, mx, my, objspace_flatness_squared, n + 1);
		stbtt__tesselate_cubic(points, num_points, mx, my, xb, yb, x23, y23, x3, y3, objspace_flatness_squared, n + 1);
	}
	else {
		stbtt__add_point(points, *num_points, x3, y3);
		*num_points = *num_points + 1;
	}
}

// returns number of contours
static stbtt__point *stbtt_FlattenCurves(stbtt_vertex *vertices, int num_verts, float objspace_flatness, int **contour_lengths, int *num_contours, void *userdata)
{
	stbtt__point *points = 0;
	int num_points = 0;

	float objspace_flatness_squared = objspace_flatness * objspace_flatness;
	int i, n = 0, start = 0, pass;

	// count how many "moves" there are to get the contour count
	for (i = 0; i < num_verts; ++i)
		if (vertices[i].type == STBTT_vmove)
			++n;

	*num_contours = n;
	if (n == 0) return 0;

	*contour_lengths = (int *)STBTT_malloc(sizeof(**contour_lengths) * n, userdata);

	if (*contour_lengths == 0) {
		*num_contours = 0;
		return 0;
	}

	// make two passes through the points so we don't need to realloc
	for (pass = 0; pass < 2; ++pass) {
		float x = 0, y = 0;
		if (pass == 1) {
			points = (stbtt__point *)STBTT_malloc(num_points * sizeof(points[0]), userdata);
			if (points == NULL) goto error;
		}
		num_points = 0;
		n = -1;
		for (i = 0; i < num_verts; ++i) {
			switch (vertices[i].type) {
			case STBTT_vmove:
				// start the next contour
				if (n >= 0)
					(*contour_lengths)[n] = num_points - start;
				++n;
				start = num_points;

				x = vertices[i].x, y = vertices[i].y;
				stbtt__add_point(points, num_points++, x, y);
				break;
			case STBTT_vline:
				x = vertices[i].x, y = vertices[i].y;
				stbtt__add_point(points, num_points++, x, y);
				break;
			case STBTT_vcurve:
				stbtt__tesselate_curve(points, &num_points, x, y,
					vertices[i].cx, vertices[i].cy,
					vertices[i].x, vertices[i].y,
					objspace_flatness_squared, 0);
				x = vertices[i].x, y = vertices[i].y;
				break;
			case STBTT_vcubic:
				stbtt__tesselate_cubic(points, &num_points, x, y,
					vertices[i].cx, vertices[i].cy,
					vertices[i].cx1, vertices[i].cy1,
					vertices[i].x, vertices[i].y,
					objspace_flatness_squared, 0);
				x = vertices[i].x, y = vertices[i].y;
				break;
			}
		}
		(*contour_lengths)[n] = num_points - start;
	}

	return points;
error:
	STBTT_free(points, userdata);
	STBTT_free(*contour_lengths, userdata);
	*contour_lengths = 0;
	*num_contours = 0;
	return NULL;
}

STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result, float flatness_in_pixels, stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata)
{
	float scale = scale_x > scale_y ? scale_y : scale_x;
	int winding_count, *winding_lengths;
	stbtt__point *windings = stbtt_FlattenCurves(vertices, num_verts, flatness_in_pixels / scale, &winding_lengths, &winding_count, userdata);
	if (windings) {
		stbtt__rasterize(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata);
		STBTT_free(winding_lengths, userdata);
		STBTT_free(windings, userdata);
	}
}

STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata)
{
	STBTT_free(bitmap, userdata);
}

STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff)
{
	int ix0, iy0, ix1, iy1;
	stbtt__bitmap gbm;
	stbtt_vertex *vertices;
	int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);

	if (scale_x == 0) scale_x = scale_y;
	if (scale_y == 0) {
		if (scale_x == 0) {
			STBTT_free(vertices, info->userdata);
			return NULL;
		}
		scale_y = scale_x;
	}

	stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0, &iy0, &ix1, &iy1);

	// now we get the size
	gbm.w = (ix1 - ix0);
	gbm.h = (iy1 - iy0);
	gbm.pixels = NULL; // in case we error

	if (width) *width = gbm.w;
	if (height) *height = gbm.h;
	if (xoff) *xoff = ix0;
	if (yoff) *yoff = iy0;

	if (gbm.w && gbm.h) {
		gbm.pixels = (unsigned char *)STBTT_malloc(gbm.w * gbm.h, info->userdata);
		if (gbm.pixels) {
			gbm.stride = gbm.w;

			stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);
		}
	}
	STBTT_free(vertices, info->userdata);
	return gbm.pixels;
}

STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff)
{
	return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y, 0.0f, 0.0f, glyph, width, height, xoff, yoff);
}

STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph)
{
	int ix0, iy0;
	stbtt_vertex *vertices;
	int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);
	stbtt__bitmap gbm;

	stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0, &iy0, 0, 0);
	gbm.pixels = output;
	gbm.w = out_w;
	gbm.h = out_h;
	gbm.stride = out_stride;

	if (gbm.w && gbm.h)
		stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);

	STBTT_free(vertices, info->userdata);
}

STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph)
{
	stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f, 0.0f, glyph);
}

STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
{
	return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y, shift_x, shift_y, stbtt_FindGlyphIndex(info, codepoint), width, height, xoff, yoff);
}

STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint)
{
	stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, stbtt_FindGlyphIndex(info, codepoint));
}

STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
{
	return stbtt_GetCodepointBitmapSubpixel(info, scale_x, scale_y, 0.0f, 0.0f, codepoint, width, height, xoff, yoff);
}

STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint)
{
	stbtt_MakeCodepointBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f, 0.0f, codepoint);
}

//////////////////////////////////////////////////////////////////////////////
//
// bitmap baking
//
// This is SUPER-CRAPPY packing to keep source code small

static int stbtt_BakeFontBitmap_internal(unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
	float pixel_height,                     // height of font in pixels
	unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
	int first_char, int num_chars,          // characters to bake
	stbtt_bakedchar *chardata)
{
	float scale;
	int x, y, bottom_y, i;
	stbtt_fontinfo f;
	f.userdata = NULL;
	if (!stbtt_InitFont(&f, data, offset))
		return -1;
	STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
	x = y = 1;
	bottom_y = 1;

	scale = stbtt_ScaleForPixelHeight(&f, pixel_height);

	for (i = 0; i < num_chars; ++i) {
		int advance, lsb, x0, y0, x1, y1, gw, gh;
		int g = stbtt_FindGlyphIndex(&f, first_char + i);
		stbtt_GetGlyphHMetrics(&f, g, &advance, &lsb);
		stbtt_GetGlyphBitmapBox(&f, g, scale, scale, &x0, &y0, &x1, &y1);
		gw = x1 - x0;
		gh = y1 - y0;
		if (x + gw + 1 >= pw)
			y = bottom_y, x = 1; // advance to next row
		if (y + gh + 1 >= ph) // check if it fits vertically AFTER potentially moving to next row
			return -i;
		STBTT_assert(x + gw < pw);
		STBTT_assert(y + gh < ph);
		stbtt_MakeGlyphBitmap(&f, pixels + x + y*pw, gw, gh, pw, scale, scale, g);
		chardata[i].x0 = (stbtt_int16)x;
		chardata[i].y0 = (stbtt_int16)y;
		chardata[i].x1 = (stbtt_int16)(x + gw);
		chardata[i].y1 = (stbtt_int16)(y + gh);
		chardata[i].xadvance = scale * advance;
		chardata[i].xoff = (float)x0;
		chardata[i].yoff = (float)y0;
		x = x + gw + 1;
		if (y + gh + 1 > bottom_y)
			bottom_y = y + gh + 1;
	}
	return bottom_y;
}

STBTT_DEF void stbtt_GetBakedQuad(stbtt_bakedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int opengl_fillrule)
{
	float d3d_bias = opengl_fillrule ? 0 : -0.5f;
	float ipw = 1.0f / pw, iph = 1.0f / ph;
	stbtt_bakedchar *b = chardata + char_index;
	int round_x = STBTT_ifloor((*xpos + b->xoff) + 0.5f);
	int round_y = STBTT_ifloor((*ypos + b->yoff) + 0.5f);

	q->x0 = round_x + d3d_bias;
	q->y0 = round_y + d3d_bias;
	q->x1 = round_x + b->x1 - b->x0 + d3d_bias;
	q->y1 = round_y + b->y1 - b->y0 + d3d_bias;

	q->s0 = b->x0 * ipw;
	q->t0 = b->y0 * iph;
	q->s1 = b->x1 * ipw;
	q->t1 = b->y1 * iph;

	*xpos += b->xadvance;
}

//////////////////////////////////////////////////////////////////////////////
//
// rectangle packing replacement routines if you don't have stb_rect_pack.h
//

#ifndef STB_RECT_PACK_VERSION

typedef int stbrp_coord;

////////////////////////////////////////////////////////////////////////////////////
//                                                                                //
//                                                                                //
// COMPILER WARNING ?!?!?                                                         //
//                                                                                //
//                                                                                //
// if you get a compile warning due to these symbols being defined more than      //
// once, move #include "stb_rect_pack.h" before #include "stb_truetype.h"         //
//                                                                                //
////////////////////////////////////////////////////////////////////////////////////

typedef struct
{
	int width, height;
	int x, y, bottom_y;
} stbrp_context;

typedef struct
{
	unsigned char x;
} stbrp_node;

struct stbrp_rect
{
	stbrp_coord x, y;
	int id, w, h, was_packed;
};

static void stbrp_init_target(stbrp_context *con, int pw, int ph, stbrp_node *nodes, int num_nodes)
{
	con->width = pw;
	con->height = ph;
	con->x = 0;
	con->y = 0;
	con->bottom_y = 0;
	STBTT__NOTUSED(nodes);
	STBTT__NOTUSED(num_nodes);
}

static void stbrp_pack_rects(stbrp_context *con, stbrp_rect *rects, int num_rects)
{
	int i;
	for (i = 0; i < num_rects; ++i) {
		if (con->x + rects[i].w > con->width) {
			con->x = 0;
			con->y = con->bottom_y;
		}
		if (con->y + rects[i].h > con->height)
			break;
		rects[i].x = con->x;
		rects[i].y = con->y;
		rects[i].was_packed = 1;
		con->x += rects[i].w;
		if (con->y + rects[i].h > con->bottom_y)
			con->bottom_y = con->y + rects[i].h;
	}
	for (; i < num_rects; ++i)
		rects[i].was_packed = 0;
}
#endif

//////////////////////////////////////////////////////////////////////////////
//
// bitmap baking
//
// This is SUPER-AWESOME (tm Ryan Gordon) packing using stb_rect_pack.h. If
// stb_rect_pack.h isn't available, it uses the BakeFontBitmap strategy.

STBTT_DEF int stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int pw, int ph, int stride_in_bytes, int padding, void *alloc_context)
{
	stbrp_context *context = (stbrp_context *)STBTT_malloc(sizeof(*context), alloc_context);
	int            num_nodes = pw - padding;
	stbrp_node    *nodes = (stbrp_node    *)STBTT_malloc(sizeof(*nodes) * num_nodes, alloc_context);

	if (context == NULL || nodes == NULL) {
		if (context != NULL) STBTT_free(context, alloc_context);
		if (nodes != NULL) STBTT_free(nodes, alloc_context);
		return 0;
	}

	spc->user_allocator_context = alloc_context;
	spc->width = pw;
	spc->height = ph;
	spc->pixels = pixels;
	spc->pack_info = context;
	spc->nodes = nodes;
	spc->padding = padding;
	spc->stride_in_bytes = stride_in_bytes != 0 ? stride_in_bytes : pw;
	spc->h_oversample = 1;
	spc->v_oversample = 1;

	stbrp_init_target(context, pw - padding, ph - padding, nodes, num_nodes);

	if (pixels)
		STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels

	return 1;
}

STBTT_DEF void stbtt_PackEnd(stbtt_pack_context *spc)
{
	STBTT_free(spc->nodes, spc->user_allocator_context);
	STBTT_free(spc->pack_info, spc->user_allocator_context);
}

STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample)
{
	STBTT_assert(h_oversample <= STBTT_MAX_OVERSAMPLE);
	STBTT_assert(v_oversample <= STBTT_MAX_OVERSAMPLE);
	if (h_oversample <= STBTT_MAX_OVERSAMPLE)
		spc->h_oversample = h_oversample;
	if (v_oversample <= STBTT_MAX_OVERSAMPLE)
		spc->v_oversample = v_oversample;
}

#define STBTT__OVER_MASK  (STBTT_MAX_OVERSAMPLE-1)

static void stbtt__h_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
{
	unsigned char buffer[STBTT_MAX_OVERSAMPLE];
	int safe_w = w - kernel_width;
	int j;
	STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
	for (j = 0; j < h; ++j) {
		int i;
		unsigned int total;
		STBTT_memset(buffer, 0, kernel_width);

		total = 0;

		// make kernel_width a constant in common cases so compiler can optimize out the divide
		switch (kernel_width) {
		case 2:
			for (i = 0; i <= safe_w; ++i) {
				total += pixels[i] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i];
				pixels[i] = (unsigned char)(total / 2);
			}
			break;
		case 3:
			for (i = 0; i <= safe_w; ++i) {
				total += pixels[i] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i];
				pixels[i] = (unsigned char)(total / 3);
			}
			break;
		case 4:
			for (i = 0; i <= safe_w; ++i) {
				total += pixels[i] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i];
				pixels[i] = (unsigned char)(total / 4);
			}
			break;
		case 5:
			for (i = 0; i <= safe_w; ++i) {
				total += pixels[i] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i];
				pixels[i] = (unsigned char)(total / 5);
			}
			break;
		default:
			for (i = 0; i <= safe_w; ++i) {
				total += pixels[i] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i];
				pixels[i] = (unsigned char)(total / kernel_width);
			}
			break;
		}

		for (; i < w; ++i) {
			STBTT_assert(pixels[i] == 0);
			total -= buffer[i & STBTT__OVER_MASK];
			pixels[i] = (unsigned char)(total / kernel_width);
		}

		pixels += stride_in_bytes;
	}
}

static void stbtt__v_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
{
	unsigned char buffer[STBTT_MAX_OVERSAMPLE];
	int safe_h = h - kernel_width;
	int j;
	STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
	for (j = 0; j < w; ++j) {
		int i;
		unsigned int total;
		STBTT_memset(buffer, 0, kernel_width);

		total = 0;

		// make kernel_width a constant in common cases so compiler can optimize out the divide
		switch (kernel_width) {
		case 2:
			for (i = 0; i <= safe_h; ++i) {
				total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
				pixels[i*stride_in_bytes] = (unsigned char)(total / 2);
			}
			break;
		case 3:
			for (i = 0; i <= safe_h; ++i) {
				total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
				pixels[i*stride_in_bytes] = (unsigned char)(total / 3);
			}
			break;
		case 4:
			for (i = 0; i <= safe_h; ++i) {
				total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
				pixels[i*stride_in_bytes] = (unsigned char)(total / 4);
			}
			break;
		case 5:
			for (i = 0; i <= safe_h; ++i) {
				total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
				pixels[i*stride_in_bytes] = (unsigned char)(total / 5);
			}
			break;
		default:
			for (i = 0; i <= safe_h; ++i) {
				total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
				buffer[(i + kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
				pixels[i*stride_in_bytes] = (unsigned char)(total / kernel_width);
			}
			break;
		}

		for (; i < h; ++i) {
			STBTT_assert(pixels[i*stride_in_bytes] == 0);
			total -= buffer[i & STBTT__OVER_MASK];
			pixels[i*stride_in_bytes] = (unsigned char)(total / kernel_width);
		}

		pixels += 1;
	}
}

static float stbtt__oversample_shift(int oversample)
{
	if (!oversample)
		return 0.0f;

	// The prefilter is a box filter of width "oversample",
	// which shifts phase by (oversample - 1)/2 pixels in
	// oversampled space. We want to shift in the opposite
	// direction to counter this.
	return (float)-(oversample - 1) / (2.0f * (float)oversample);
}

// rects array must be big enough to accommodate all characters in the given ranges
STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
{
	int i, j, k;

	k = 0;
	for (i = 0; i < num_ranges; ++i) {
		float fh = ranges[i].font_size;
		float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
		ranges[i].h_oversample = (unsigned char)spc->h_oversample;
		ranges[i].v_oversample = (unsigned char)spc->v_oversample;
		for (j = 0; j < ranges[i].num_chars; ++j) {
			int x0, y0, x1, y1;
			int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
			int glyph = stbtt_FindGlyphIndex(info, codepoint);
			stbtt_GetGlyphBitmapBoxSubpixel(info, glyph,
				scale * spc->h_oversample,
				scale * spc->v_oversample,
				0, 0,
				&x0, &y0, &x1, &y1);
			rects[k].w = (stbrp_coord)(x1 - x0 + spc->padding + spc->h_oversample - 1);
			rects[k].h = (stbrp_coord)(y1 - y0 + spc->padding + spc->v_oversample - 1);
			++k;
		}
	}

	return k;
}

// rects array must be big enough to accommodate all characters in the given ranges
STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
{
	int i, j, k, return_value = 1;

	// save current values
	int old_h_over = spc->h_oversample;
	int old_v_over = spc->v_oversample;

	k = 0;
	for (i = 0; i < num_ranges; ++i) {
		float fh = ranges[i].font_size;
		float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
		float recip_h, recip_v, sub_x, sub_y;
		spc->h_oversample = ranges[i].h_oversample;
		spc->v_oversample = ranges[i].v_oversample;
		recip_h = 1.0f / spc->h_oversample;
		recip_v = 1.0f / spc->v_oversample;
		sub_x = stbtt__oversample_shift(spc->h_oversample);
		sub_y = stbtt__oversample_shift(spc->v_oversample);
		for (j = 0; j < ranges[i].num_chars; ++j) {
			stbrp_rect *r = &rects[k];
			if (r->was_packed) {
				stbtt_packedchar *bc = &ranges[i].chardata_for_range[j];
				int advance, lsb, x0, y0, x1, y1;
				int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
				int glyph = stbtt_FindGlyphIndex(info, codepoint);
				stbrp_coord pad = (stbrp_coord)spc->padding;

				// pad on left and top
				r->x += pad;
				r->y += pad;
				r->w -= pad;
				r->h -= pad;
				stbtt_GetGlyphHMetrics(info, glyph, &advance, &lsb);
				stbtt_GetGlyphBitmapBox(info, glyph,
					scale * spc->h_oversample,
					scale * spc->v_oversample,
					&x0, &y0, &x1, &y1);
				stbtt_MakeGlyphBitmapSubpixel(info,
					spc->pixels + r->x + r->y*spc->stride_in_bytes,
					r->w - spc->h_oversample + 1,
					r->h - spc->v_oversample + 1,
					spc->stride_in_bytes,
					scale * spc->h_oversample,
					scale * spc->v_oversample,
					0, 0,
					glyph);

				if (spc->h_oversample > 1)
					stbtt__h_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
						r->w, r->h, spc->stride_in_bytes,
						spc->h_oversample);

				if (spc->v_oversample > 1)
					stbtt__v_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
						r->w, r->h, spc->stride_in_bytes,
						spc->v_oversample);

				bc->x0 = (stbtt_int16)r->x;
				bc->y0 = (stbtt_int16)r->y;
				bc->x1 = (stbtt_int16)(r->x + r->w);
				bc->y1 = (stbtt_int16)(r->y + r->h);
				bc->xadvance = scale * advance;
				bc->xoff = (float)x0 * recip_h + sub_x;
				bc->yoff = (float)y0 * recip_v + sub_y;
				bc->xoff2 = (x0 + r->w) * recip_h + sub_x;
				bc->yoff2 = (y0 + r->h) * recip_v + sub_y;
			}
			else {
				return_value = 0; // if any fail, report failure
			}

			++k;
		}
	}

	// restore original values
	spc->h_oversample = old_h_over;
	spc->v_oversample = old_v_over;

	return return_value;
}

STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects)
{
	stbrp_pack_rects((stbrp_context *)spc->pack_info, rects, num_rects);
}

STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges)
{
	stbtt_fontinfo info;
	int i, j, n, return_value = 1;
	//stbrp_context *context = (stbrp_context *) spc->pack_info;
	stbrp_rect    *rects;

	// flag all characters as NOT packed
	for (i = 0; i < num_ranges; ++i)
		for (j = 0; j < ranges[i].num_chars; ++j)
			ranges[i].chardata_for_range[j].x0 =
			ranges[i].chardata_for_range[j].y0 =
			ranges[i].chardata_for_range[j].x1 =
			ranges[i].chardata_for_range[j].y1 = 0;

	n = 0;
	for (i = 0; i < num_ranges; ++i)
		n += ranges[i].num_chars;

	rects = (stbrp_rect *)STBTT_malloc(sizeof(*rects) * n, spc->user_allocator_context);
	if (rects == NULL)
		return 0;

	info.userdata = spc->user_allocator_context;
	stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata, font_index));

	n = stbtt_PackFontRangesGatherRects(spc, &info, ranges, num_ranges, rects);

	stbtt_PackFontRangesPackRects(spc, rects, n);

	return_value = stbtt_PackFontRangesRenderIntoRects(spc, &info, ranges, num_ranges, rects);

	STBTT_free(rects, spc->user_allocator_context);
	return return_value;
}

STBTT_DEF int stbtt_PackFontRange(stbtt_pack_context *spc, unsigned char *fontdata, int font_index, float font_size,
	int first_unicode_codepoint_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range)
{
	stbtt_pack_range range;
	range.first_unicode_codepoint_in_range = first_unicode_codepoint_in_range;
	range.array_of_unicode_codepoints = NULL;
	range.num_chars = num_chars_in_range;
	range.chardata_for_range = chardata_for_range;
	range.font_size = font_size;
	return stbtt_PackFontRanges(spc, fontdata, font_index, &range, 1);
}

STBTT_DEF void stbtt_GetPackedQuad(stbtt_packedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int align_to_integer)
{
	float ipw = 1.0f / pw, iph = 1.0f / ph;
	stbtt_packedchar *b = chardata + char_index;

	if (align_to_integer) {
		float x = (float)STBTT_ifloor((*xpos + b->xoff) + 0.5f);
		float y = (float)STBTT_ifloor((*ypos + b->yoff) + 0.5f);
		q->x0 = x;
		q->y0 = y;
		q->x1 = x + b->xoff2 - b->xoff;
		q->y1 = y + b->yoff2 - b->yoff;
	}
	else {
		q->x0 = *xpos + b->xoff;
		q->y0 = *ypos + b->yoff;
		q->x1 = *xpos + b->xoff2;
		q->y1 = *ypos + b->yoff2;
	}

	q->s0 = b->x0 * ipw;
	q->t0 = b->y0 * iph;
	q->s1 = b->x1 * ipw;
	q->t1 = b->y1 * iph;

	*xpos += b->xadvance;
}


//////////////////////////////////////////////////////////////////////////////
//
// font name matching -- recommended not to use this
//

// check if a utf8 string contains a prefix which is the utf16 string; if so return length of matching utf8 string
static stbtt_int32 stbtt__CompareUTF8toUTF16_bigendian_prefix(stbtt_uint8 *s1, stbtt_int32 len1, stbtt_uint8 *s2, stbtt_int32 len2)
{
	stbtt_int32 i = 0;

	// convert utf16 to utf8 and compare the results while converting
	while (len2) {
		stbtt_uint16 ch = s2[0] * 256 + s2[1];
		if (ch < 0x80) {
			if (i >= len1) return -1;
			if (s1[i++] != ch) return -1;
		}
		else if (ch < 0x800) {
			if (i + 1 >= len1) return -1;
			if (s1[i++] != 0xc0 + (ch >> 6)) return -1;
			if (s1[i++] != 0x80 + (ch & 0x3f)) return -1;
		}
		else if (ch >= 0xd800 && ch < 0xdc00) {
			stbtt_uint32 c;
			stbtt_uint16 ch2 = s2[2] * 256 + s2[3];
			if (i + 3 >= len1) return -1;
			c = ((ch - 0xd800) << 10) + (ch2 - 0xdc00) + 0x10000;
			if (s1[i++] != 0xf0 + (c >> 18)) return -1;
			if (s1[i++] != 0x80 + ((c >> 12) & 0x3f)) return -1;
			if (s1[i++] != 0x80 + ((c >> 6) & 0x3f)) return -1;
			if (s1[i++] != 0x80 + ((c) & 0x3f)) return -1;
			s2 += 2; // plus another 2 below
			len2 -= 2;
		}
		else if (ch >= 0xdc00 && ch < 0xe000) {
			return -1;
		}
		else {
			if (i + 2 >= len1) return -1;
			if (s1[i++] != 0xe0 + (ch >> 12)) return -1;
			if (s1[i++] != 0x80 + ((ch >> 6) & 0x3f)) return -1;
			if (s1[i++] != 0x80 + ((ch) & 0x3f)) return -1;
		}
		s2 += 2;
		len2 -= 2;
	}
	return i;
}

static int stbtt_CompareUTF8toUTF16_bigendian_internal(char *s1, int len1, char *s2, int len2)
{
	return len1 == stbtt__CompareUTF8toUTF16_bigendian_prefix((stbtt_uint8*)s1, len1, (stbtt_uint8*)s2, len2);
}

// returns results in whatever encoding you request... but note that 2-byte encodings
// will be BIG-ENDIAN... use stbtt_CompareUTF8toUTF16_bigendian() to compare
STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID)
{
	stbtt_int32 i, count, stringOffset;
	stbtt_uint8 *fc = font->data;
	stbtt_uint32 offset = font->fontstart;
	stbtt_uint32 nm = stbtt__find_table(fc, offset, "name");
	if (!nm) return NULL;

	count = ttUSHORT(fc + nm + 2);
	stringOffset = nm + ttUSHORT(fc + nm + 4);
	for (i = 0; i < count; ++i) {
		stbtt_uint32 loc = nm + 6 + 12 * i;
		if (platformID == ttUSHORT(fc + loc + 0) && encodingID == ttUSHORT(fc + loc + 2)
			&& languageID == ttUSHORT(fc + loc + 4) && nameID == ttUSHORT(fc + loc + 6)) {
			*length = ttUSHORT(fc + loc + 8);
			return (const char *)(fc + stringOffset + ttUSHORT(fc + loc + 10));
		}
	}
	return NULL;
}

static int stbtt__matchpair(stbtt_uint8 *fc, stbtt_uint32 nm, stbtt_uint8 *name, stbtt_int32 nlen, stbtt_int32 target_id, stbtt_int32 next_id)
{
	stbtt_int32 i;
	stbtt_int32 count = ttUSHORT(fc + nm + 2);
	stbtt_int32 stringOffset = nm + ttUSHORT(fc + nm + 4);

	for (i = 0; i < count; ++i) {
		stbtt_uint32 loc = nm + 6 + 12 * i;
		stbtt_int32 id = ttUSHORT(fc + loc + 6);
		if (id == target_id) {
			// find the encoding
			stbtt_int32 platform = ttUSHORT(fc + loc + 0), encoding = ttUSHORT(fc + loc + 2), language = ttUSHORT(fc + loc + 4);

			// is this a Unicode encoding?
			if (platform == 0 || (platform == 3 && encoding == 1) || (platform == 3 && encoding == 10)) {
				stbtt_int32 slen = ttUSHORT(fc + loc + 8);
				stbtt_int32 off = ttUSHORT(fc + loc + 10);

				// check if there's a prefix match
				stbtt_int32 matchlen = stbtt__CompareUTF8toUTF16_bigendian_prefix(name, nlen, fc + stringOffset + off, slen);
				if (matchlen >= 0) {
					// check for target_id+1 immediately following, with same encoding & language
					if (i + 1 < count && ttUSHORT(fc + loc + 12 + 6) == next_id && ttUSHORT(fc + loc + 12) == platform && ttUSHORT(fc + loc + 12 + 2) == encoding && ttUSHORT(fc + loc + 12 + 4) == language) {
						slen = ttUSHORT(fc + loc + 12 + 8);
						off = ttUSHORT(fc + loc + 12 + 10);
						if (slen == 0) {
							if (matchlen == nlen)
								return 1;
						}
						else if (matchlen < nlen && name[matchlen] == ' ') {
							++matchlen;
							if (stbtt_CompareUTF8toUTF16_bigendian_internal((char*)(name + matchlen), nlen - matchlen, (char*)(fc + stringOffset + off), slen))
								return 1;
						}
					}
					else {
						// if nothing immediately following
						if (matchlen == nlen)
							return 1;
					}
				}
			}

			// @TODO handle other encodings
		}
	}
	return 0;
}

static int stbtt__matches(stbtt_uint8 *fc, stbtt_uint32 offset, stbtt_uint8 *name, stbtt_int32 flags)
{
	stbtt_int32 nlen = (stbtt_int32)STBTT_strlen((char *)name);
	stbtt_uint32 nm, hd;
	if (!stbtt__isfont(fc + offset)) return 0;

	// check italics/bold/underline flags in macStyle...
	if (flags) {
		hd = stbtt__find_table(fc, offset, "head");
		if ((ttUSHORT(fc + hd + 44) & 7) != (flags & 7)) return 0;
	}

	nm = stbtt__find_table(fc, offset, "name");
	if (!nm) return 0;

	if (flags) {
		// if we checked the macStyle flags, then just check the family and ignore the subfamily
		if (stbtt__matchpair(fc, nm, name, nlen, 16, -1))  return 1;
		if (stbtt__matchpair(fc, nm, name, nlen, 1, -1))  return 1;
		if (stbtt__matchpair(fc, nm, name, nlen, 3, -1))  return 1;
	}
	else {
		if (stbtt__matchpair(fc, nm, name, nlen, 16, 17))  return 1;
		if (stbtt__matchpair(fc, nm, name, nlen, 1, 2))  return 1;
		if (stbtt__matchpair(fc, nm, name, nlen, 3, -1))  return 1;
	}

	return 0;
}

static int stbtt_FindMatchingFont_internal(unsigned char *font_collection, char *name_utf8, stbtt_int32 flags)
{
	stbtt_int32 i;
	for (i = 0;; ++i) {
		stbtt_int32 off = stbtt_GetFontOffsetForIndex(font_collection, i);
		if (off < 0) return off;
		if (stbtt__matches((stbtt_uint8 *)font_collection, off, (stbtt_uint8*)name_utf8, flags))
			return off;
	}
}

#if defined(__GNUC__) || defined(__clang__)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-qual"
#endif

STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,
	float pixel_height, unsigned char *pixels, int pw, int ph,
	int first_char, int num_chars, stbtt_bakedchar *chardata)
{
	return stbtt_BakeFontBitmap_internal((unsigned char *)data, offset, pixel_height, pixels, pw, ph, first_char, num_chars, chardata);
}

STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index)
{
	return stbtt_GetFontOffsetForIndex_internal((unsigned char *)data, index);
}

STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data)
{
	return stbtt_GetNumberOfFonts_internal((unsigned char *)data);
}

STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset)
{
	return stbtt_InitFont_internal(info, (unsigned char *)data, offset);
}

STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags)
{
	return stbtt_FindMatchingFont_internal((unsigned char *)fontdata, (char *)name, flags);
}

STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2)
{
	return stbtt_CompareUTF8toUTF16_bigendian_internal((char *)s1, len1, (char *)s2, len2);
}

#if defined(__GNUC__) || defined(__clang__)
#pragma GCC diagnostic pop
#endif

#endif // STB_TRUETYPE_IMPLEMENTATION


// FULL VERSION HISTORY
//
//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
//   1.11 (2016-04-02) fix unused-variable warning
//   1.10 (2016-04-02) allow user-defined fabs() replacement
//                     fix memory leak if fontsize=0.0
//                     fix warning from duplicate typedef
//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use alloc userdata for PackFontRanges
//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
//                     allow PackFontRanges to pack and render in separate phases;
//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
//                     fixed an assert() bug in the new rasterizer
//                     replace assert() with STBTT_assert() in new rasterizer
//   1.06 (2015-07-14) performance improvements (~35% faster on x86 and x64 on test machine)
//                     also more precise AA rasterizer, except if shapes overlap
//                     remove need for STBTT_sort
//   1.05 (2015-04-15) fix misplaced definitions for STBTT_STATIC
//   1.04 (2015-04-15) typo in example
//   1.03 (2015-04-12) STBTT_STATIC, fix memory leak in new packing, various fixes
//   1.02 (2014-12-10) fix various warnings & compile issues w/ stb_rect_pack, C++
//   1.01 (2014-12-08) fix subpixel position when oversampling to exactly match
//                        non-oversampled; STBTT_POINT_SIZE for packed case only
//   1.00 (2014-12-06) add new PackBegin etc. API, w/ support for oversampling
//   0.99 (2014-09-18) fix multiple bugs with subpixel rendering (ryg)
//   0.9  (2014-08-07) support certain mac/iOS fonts without an MS platformID
//   0.8b (2014-07-07) fix a warning
//   0.8  (2014-05-25) fix a few more warnings
//   0.7  (2013-09-25) bugfix: subpixel glyph bug fixed in 0.5 had come back
//   0.6c (2012-07-24) improve documentation
//   0.6b (2012-07-20) fix a few more warnings
//   0.6  (2012-07-17) fix warnings; added stbtt_ScaleForMappingEmToPixels,
//                        stbtt_GetFontBoundingBox, stbtt_IsGlyphEmpty
//   0.5  (2011-12-09) bugfixes:
//                        subpixel glyph renderer computed wrong bounding box
//                        first vertex of shape can be off-curve (FreeSans)
//   0.4b (2011-12-03) fixed an error in the font baking example
//   0.4  (2011-12-01) kerning, subpixel rendering (tor)
//                    bugfixes for:
//                        codepoint-to-glyph conversion using table fmt=12
//                        codepoint-to-glyph conversion using table fmt=4
//                        stbtt_GetBakedQuad with non-square texture (Zer)
//                    updated Hello World! sample to use kerning and subpixel
//                    fixed some warnings
//   0.3  (2009-06-24) cmap fmt=12, compound shapes (MM)
//                    userdata, malloc-from-userdata, non-zero fill (stb)
//   0.2  (2009-03-11) Fix unsigned/signed char warnings
//   0.1  (2009-03-09) First public release
//
